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1.
Sci Rep ; 13(1): 9757, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37328489

RESUMEN

Underground Coal Gasification (UCG) requires monitoring of the gasification area because the gasification process is invisible and the reaction temperature exceeds 1000 °C. Many fracturing events that occurred due to coal heating can be captured with Acoustic Emission (AE) monitoring technique during UCG. However, the temperature conditions to generate fracturing events during UCG have not yet been clarified. Therefore, the coal heating experiment and small-scale UCG experiment are conducted by measuring the temperature and AE activities in this research to examine the applicability of the AE technique instead of temperature measurement as a monitoring method during UCG. As a result, many fracturing events are generated when the temperature of coal is changed drastically, especially during coal gasification. Besides, AE events increase in the sensor near the heat source and AE sources are expanded widely with the expansion of the high-temperature region. AE monitoring is an effective technique for the estimation of the gasification area during UCG instead of temperature monitoring.


Asunto(s)
Carbón Mineral , Calor , Temperatura
2.
Sci Rep ; 8(1): 16472, 2018 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-30405204

RESUMEN

The amount of water drainage from Kushiro Coal Mine in Hokkaido, Japan decreased on the day of all M ≥ 7.5 earthquakes with epicenters within 300 km of the mine during the monitoring period and increased after these earthquakes. This is a valuable finding which would give us a clue to understand pre- and post-seismic rockmass behaviors and contribute for progress in earthquake prediction in future.

3.
Sensors (Basel) ; 16(8)2016 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-27490544

RESUMEN

Joint moment estimation by a camera-based motion measurement system and a force plate has a limitation of measurement environment and is costly. The purpose of this paper is to evaluate quantitatively inertial sensor-based joint moment estimation methods with five-link, four-link and three-link rigid body models using different trunk segmented models. Joint moments, ground reaction forces (GRF) and center of pressure (CoP) were estimated for squat and sit-to-stand movements in the sagittal plane measured with six healthy subjects. The five-link model and the four-link model that the trunk was divided at the highest point of the iliac crest (four-link-IC model) were appropriate for joint moment estimation with inertial sensors, which showed average RMS values of about 0.1 Nm/kg for all lower limb joints and average correlation coefficients of about 0.98 for hip and knee joints and about 0.80 for ankle joint. Average root mean square (RMS) errors of horizontal and vertical GRFs and CoP were about 10 N, 15 N and 2 cm, respectively. Inertial sensor-based method was suggested to be an option for estimating joint moments of the trunk segments. Inertial sensors were also shown to be useful for the bottom-up estimation method using measured GRFs, in which average RMS values and average correlation coefficients were about 0.06 Nm/kg and larger than about 0.98 for all joints.


Asunto(s)
Articulación del Tobillo/fisiología , Extremidad Inferior/fisiología , Movimiento/fisiología , Postura/fisiología , Adulto , Fenómenos Biomecánicos , Simulación por Computador , Femenino , Marcha/fisiología , Humanos , Articulación de la Rodilla/fisiología , Modelos Biológicos
4.
Med Mycol J ; 54(2): 131-40, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23760077

RESUMEN

We previously developed an N-acetyl-D-glucosamine (GlcNAc) medium which induces Candida albicans to undergo a yeast-to-hyphal transition through a cAMP-PKA pathway. Microarray analysis demonstrated that 18 genes, including ALS3 that encodes a cell wall adhesion, were upregulated by 30-min incubation of yeast cells at 37°C in the GlcNAc medium. To investigate the differences between morphological transition and morphotype in C. albicans as a consequence of infection, this study utilized a silkworm infection model as an invertebrate mini-host. We prepared 3 different conditions of C. albicans cells in vitro by changing the incubation times in the GlcNAc medium: yeast-form cells at 0 min (Y0 cells), yeast-form cells in germination-ready state at 60 min (Y60 cells), and hyphal cells at 120 min (H120 cells), and compared their pathogenicities. We performed the infection study at various temperatures to find temperature-dependent virulence factors in vivo. Y60 cells in germination-ready state in the GlcNAc medium showed higher pathogenicity in vivo compared to Y0 and H120 cells at 30°C. Y60 cells proliferated in silkworms 24 h post-injection at 30°C, whereas the other 2 cell types did not. In vitro analysis demonstrated that Y60 cells, but not Y0 cells, germinated in the silkworm hemolymph at 30°C. However, Y0 and Y60 cells showed a similar degree of germination in the silkworm hemolymph at 37°C, although no significant difference in silkworm survival after infection with each cell type was observed at 37°C. These results suggested that the germination-ready state induced by the GlcNAc medium contributed to virulence in the silkworm.


Asunto(s)
Bombyx/microbiología , Candida albicans/patogenicidad , Animales , Modelos Animales de Enfermedad , Factores de Virulencia
5.
Biol Pharm Bull ; 35(8): 1371-3, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22863940

RESUMEN

Elevation in the temperature induces heat stress to both host cells and the invading pathogen. This study aimed to determine whether continuous mild heat stress (increased temperature without causing significant damage to host cells) can increase susceptibility of biofilm formation of the opportunistic fungal pathogen Candida albicans to low concentrations of three typical antifungal agents. In this way the side effects associated with higher concentrations of the antifungal agents on host cells would be reduced. Fluconazole and micafungin at concentrations ranging from 0.0625 to 2 µg/mL and amphotericin B at concentrations ranging from 0.0625 to 1 µg/mL inhibited less than 20% of cells in biofilm formation. Biofilm formation at 39 or 41°C compared to 37°C resulted in increased susceptibility to the three agents, but especially micafungin. These data suggest that mild heat stress (39°C) would be valuable for increasing the effectiveness of low concentrations of antifungal agents against C. albicans biofilm formation. Thus, the concept of continuous mild heat stress at the site of insertion of medical devices or catheters combined with antifungal agents could be beneficial.


Asunto(s)
Anfotericina B/farmacología , Antifúngicos/farmacología , Biopelículas/efectos de los fármacos , Candida albicans/efectos de los fármacos , Equinocandinas/farmacología , Fluconazol/farmacología , Calor , Lipopéptidos/farmacología , Estrés Fisiológico , Micafungina
6.
Biosystems ; 77(1-3): 41-6, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15527944

RESUMEN

Circadian rhythm formation is studied in seedlings after germination measuring their respiratory metabolism. The circadian rhythm is clearly observed at about 170h (the onset time t(CR-ON)) after germination of seeds in natural conditions in a dark incubator. There are no clear cyclic signals in gas exchange before t(CR-ON). Application of external triggers (temperature shocks) near the onset of the rhythm in seedling growth strongly affects formation processes. The onset is shifted earlier up to 50h by application of perturbations. This fact may suggest that the circadian rhythms appear via subcritical bifurcation.


Asunto(s)
Relojes Biológicos/fisiología , Dióxido de Carbono/metabolismo , Ritmo Circadiano/fisiología , Fabaceae/fisiología , Modelos Biológicos , Dinámicas no Lineales , Semillas/fisiología , Adaptación Fisiológica/fisiología , Respiración de la Célula/fisiología , Retroalimentación/fisiología
7.
J Clin Endocrinol Metab ; 88(9): 4446-54, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12970323

RESUMEN

Estrogen has been shown to contribute greatly to growth and development in endometrial cancer. And recent research has suggested that intratumoral production of estrogen may play important roles in this cancer tissue. On the other hand, pregnane X receptor (PXR), a new member of nuclear receptors, has been shown to mediate the genomic effects of steroid hormones, including estrogen and xenobiotics. And this receptor is thought to regulate the expression of the cytochrome P-450 3A (CYP3A) gene family, which plays important roles in the metabolism of endogenous steroids and xenobiotics. Various levels of PXR expression were found in endometrial cancer tissues but not normal tissues. Tissues showing high PXR expression showed significantly high expression of CYP3A4/7 and low expression of estrogen receptor (ER) compared with levels in tissues showing low PXR expression. In endometrial cancer cell lines, HEC-1 cells, which express high PXR and low ER and progesterone receptor, show a stronger transcriptional response of the PXR-CYP3A pathway to the PXR ligands, especially endocrine-disrupting chemical, than do Ishikawa cells. These data suggest that the steroid/xenobiotics metabolism in the tumor tissue through PXR-CYP3A pathway might play an important role, especially in alternative pathway for gonadal hormone and endocrine-disrupting chemical effects on endometrial cancer expressing low ER alpha.


Asunto(s)
Neoplasias Endometriales/metabolismo , Receptores Citoplasmáticos y Nucleares/biosíntesis , Receptores de Esteroides/biosíntesis , Hidrocarburo de Aril Hidroxilasas/biosíntesis , Hidrocarburo de Aril Hidroxilasas/genética , Western Blotting , Citocromo P-450 CYP3A , Receptor alfa de Estrógeno , Femenino , Humanos , Técnicas para Inmunoenzimas , Inmunohistoquímica , Oxidorreductasas N-Desmetilantes/biosíntesis , Oxidorreductasas N-Desmetilantes/genética , Receptor X de Pregnano , ARN Mensajero/biosíntesis , Receptores Citoplasmáticos y Nucleares/genética , Receptores de Estrógenos/biosíntesis , Receptores de Esteroides/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección , Células Tumorales Cultivadas
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