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1.
Sci Rep ; 13(1): 19748, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957265

RESUMO

In magnetic fusion plasmas, a transport barrier is essential to improve the plasma confinement. The key physics behind the formation of a transport barrier is the suppression of the micro-scale turbulent transport. On the other hand, long-range transport events, such as avalanches, has been recognized to play significant roles for global profile formations. In this study, we observed the impact of the avalanche-type of transport on the formation of a transport barrier for the first time. The avalanches are found to inhibit the formation of the internal transport barrier (ITB) observed in JT-60U tokamak. We found that (1) ITBs do not form in the presence of avalanches but form under the disappearance of avalanches, (2) the surface integral of avalanche-driven heat fluxe is comparable to the time rate change of stored energy retained at the ITB onset, (3) the mean E × B flow shear is accelerated via the ion temperature gradient that is not sustained under the existence of avalanches, and (4) after the ITB formation, avalanches are damped inside the ITB, while they remain outside the ITB.

2.
Rev Sci Instrum ; 92(5): 053505, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243237

RESUMO

We have developed a denoising autoencoder based neural network (NN) method to determine a spectral line intensity with an uncertainty lower than the uncertainty determined by fitting the spectral line. The NN method processes the measured raw spectral line shape, providing a single Gaussian shape based on the training dataset, which consists of synthetically prepared Doppler shift and broadening free spectral lines in the present work. It is found that the uncertainty reduction level significantly depends on the training dataset. Limitations originating from the training dataset are also discussed.

3.
Animal ; 12(7): 1358-1362, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29143708

RESUMO

The objective of this study was to investigate the association of single nucleotide polymorphisms (SNPs) with birth weight, weight gain from birth to weaning and from weaning to yearling, yearling height and cow weight in Nelore cattle. Data from 5064 animals participating in the DeltaGen and PAINT breeding programs were used. The animals were genotyped with a panel of 777 962 SNPs (Illumina BovineHD BeadChip) and 412 993 SNPs remained after quality control analysis of the genomic data. A genome-wide association study was performed using a single-step methodology. The analyses were processed with the BLUPF90 family of programs. When applied to a genome-wide association studies, the single-step GBLUP methodology is an iterative process that estimates weights for the SNPs. The weights of SNPs were included in all analyses by iteratively applying the single-step GBLUP methodology and repeated twice so that the effect of the SNP and the effect of the animal were recalculated in order to increase the weight of SNPs with large effects and to reduce the weight of those with small effects. The genome-wide association results are reported based on the proportion of variance explained by windows of 50 adjacent SNPs. Considering the two iterations, only windows with an additive genetic variance >1.5% were presented in the results. Associations were observed with birth weight on BTA 14, with weight gain from birth to weaning on BTA 5 and 29, with weight gain from weaning to yearling on BTA 11, and with yearling height on BTA 8, showing the genes TMEM68 (transmembrane protein 8B) associated with birth weight and yearling height, XKR4 (XK, Kell blood group complex subunit-related family, member 4) associated with birth weight, NPR2 (natriuretic peptide receptor B) associated with yearling height, and REG3G (regenerating islet-derived 3-gamma) associated with weight gain from weaning to yearling. These genes play an important role in feed intake, weight gain and the regulation of skeletal growth.


Assuntos
Cruzamento , Bovinos , Estudo de Associação Genômica Ampla , Animais , Peso Corporal , Bovinos/genética , Bovinos/crescimento & desenvolvimento , Feminino , Fenótipo , Polimorfismo de Nucleotídeo Único , Desmame , Aumento de Peso
4.
Rev Sci Instrum ; 87(11): 11D424, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910550

RESUMO

In the divertor simulation experiments in the GAMMA 10/PDX tandem mirror, pressure of the neutral gas was investigated by using a fast ionization gauge. The gauge was absolutely calibrated for hydrogen gas by using a capacitance manometer. Change of the gauge sensitivity due to the magnetic field of GAMMA 10/PDX was also evaluated. The typical gas pressure measured in detached plasma experiments was 0.1-10 Pa. The degree of plasma detachment determined from the reduction of heat flux was enhanced as the gas pressure increases. Rapid increase of the gas pressure under the plasma flow was also observed.

5.
J Anim Sci ; 93(6): 2706-13, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26115258

RESUMO

The objective of this study was to estimate genetic associations between scrotal circumference obtained at 12 (SC12; mean of 21.46 ± 2.74 cm), 15 (SC15; mean of 25.31 ± 3.19 cm), and 18 mo of age (SC18; mean of 26.77 ± 2.95 cm) and reproductive traits measured directly in heifers (age at first calving [AFC]: mean of 1,062.06 ± 114.79 d; heifer pregnancy at 16 mo of age [HP]: mean of 15.4 ± 0.36%; and subsequent rebreeding of primiparous heifers [HR]: mean of 27.1 ± 0.44%) using Bayesian inference to evaluate the possible inclusion of these traits as selection criteria in beef cattle breeding programs. Genetic gains comparisons were also estimated. A total of 53,683 data of Nelore animals born between 1990 and 2006, obtained from the livestock archive of Agropecuária Jacarezinho Ltda. (Valparaíso, São Paulo, Brazil), were analyzed. Two-trait analysis provided heritability estimates of 0.35 ± 0.08, 0.40 ± 0.04, 0.37 ± 0.03, 0.21 ± 0.01, 0.55 ± 0.03, and 0.17 ± 0.03 for SC12, SC15, SC18, AFC, HP, and HR, respectively. The genetic correlations between scrotal circumference and AFC, HP, and HR were -0.42 ± 0.12, 0.43 ± 0.13, and -0.13 ± 0.17, respectively, for SC12; -0.25 ± 0.07, 0.26 ± 0.07, and -0.11 ± 0.10, respectively, for SC15; and -0.22 ± 0.06, 0.39 ± 0.06, and 0.11 ± 0.09, respectively, for SC18. The direct selection response for HP was 0.12%, but when HP is indirectly selected based on the scrotal circumferences, the gains on these correlated responses were higher (0.16, 0.16, and 0.22%) for selection based on SC12, SC15, and SC18, respectively. These findings suggest that the selection of animals for larger scrotal circumference, particularly at 12 mo of age, should result in higher rates of HP and younger AFC of Nelore females.


Assuntos
Cruzamento/métodos , Bovinos/genética , Característica Quantitativa Herdável , Reprodução/fisiologia , Escroto/anatomia & histologia , Fatores Etários , Animais , Teorema de Bayes , Brasil , Cruzamento/normas , Bovinos/fisiologia , Feminino , Estudos de Associação Genética , Masculino , Carne , Gravidez , Reprodução/genética
6.
Animal ; 9(6): 938-43, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25684276

RESUMO

The objectives of the present study were to investigate the influence of yearling weight on the occurrence of early pregnancy and to determine differences between precocious and non-precocious heifers in terms of pre- and postnatal calf mortality, calf weight and height, mature cow weight, and stayability of the cow in the herd. Data from 26 977 females of a Nelore herd that participated in the breeding season between 1986 and 2004 were analyzed. The influence of yearling weight on sexual precocity and differences between precocious and non-precocious heifers in pre- and postnatal calf mortality and stayability were analyzed using the GENMOD procedure of the SAS program. Differences in the growth traits between precocious and non-precocious animals were estimated by contrast analysis. Three groups were analyzed for postnatal mortality: first calving of the heifers, calves born from the third calving and all offspring of the cow. In order to have a standardized calving to conception period for all females (precocious and non-precocious), calves born from the second calving were not included in the analysis. This was necessary because the first calving to conception period (days open) of precocious heifers was longer than for non-precocious due to farm reproductive management. No differences in postnatal mortality rates, from the third calving, were observed between the two groups of heifers studied. Analysis of all offspring of the dams showed a 9% higher probability of death of calves born to precocious heifers compared with calves born to non-precocious heifers. With respect to stayability, precocious heifers presented 33% greater odds to remain in the herd until 5 and 6 years of age and 28% greater odds to remain in the herd until 7 years when compared with non-precocious heifers. Precocious heifers weaned calves (205 days) significantly heavier than non-precocious ones, 1.410 and 0.797 kg considering the weaning weights of all offspring and of the third calving, respectively. With respect to sexual precocity, the results suggest that the probability of heifers to become pregnant at 16 months of age increases with increasing weight. However, heifers weighing more than 240 kg present practically the same pregnancy probability. Nevertheless, exposure of heifers during the early breeding season is recommended for beef cattle herds raised in tropical regions in view of the numerous benefits demonstrated here.


Assuntos
Peso Corporal , Bovinos/fisiologia , Longevidade , Reprodução , Maturidade Sexual , Animais , Brasil , Cruzamento , Bovinos/crescimento & desenvolvimento , Feminino , Gravidez , Estações do Ano , Aumento de Peso
7.
Calcif Tissue Int ; 60(3): 291-6, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9069168

RESUMO

Ossification of the posterior longitudinal ligament (OPLL) of the spine is characterized by heterotopic bone formation occurring in spinal ligament, causing severe compression myelopathy. In order to investigate the mechanism of OPLL development, we isolated spinal ligament cells from OPLL patients as well as non-OPLL patients, and established 10 OPLL cell lines and 7 non-OPLL cell lines, respectively. We analyzed the effects of bone morphogenetic protein-2 (BMP-2) on these cells with respect to alkaline phosphatase (AP) activity, DNA synthesis, and collagen production. BMP-2 caused a significant increase of AP activity in 4 OPLL cell lines, whereas the activity did not change in any non-OPLL cells. Among OPLL cells, BMP-2 stimulated DNA synthesis in four cell lines and procollagen type I carboxyl-terminal peptide (PICP) synthesis in five cell lines. Some non-OPLL cells also responded to BMP-2, as there was an increase of DNA synthesis in three cell lines and PICP synthesis in one cell line. These data collectively indicate that BMP-2 preferentially induces osteogenic differentiation in OPLL cells rather than in non-OPLL cells. OPLL cells, therefore, exhibit a different response to BMP-2 than non-OPLL cells, suggesting that the expression of BMP receptor(s) and/or the signal transduction initiated by BMP-2 in the spinal ligament cells of OPLL patients somewhat deviate from those in normal spinal ligament cells. Such abnormal characteristics of OPLL cells as described here provide some clues to the clarification of the pathogenesis of OPLL.


Assuntos
Proteínas Morfogenéticas Ósseas/fisiologia , Ligamentos Longitudinais/citologia , Ossificação do Ligamento Longitudinal Posterior/fisiopatologia , Fator de Crescimento Transformador beta , Fatores de Crescimento Transformadores/fisiologia , Fosfatase Alcalina/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Proteína Morfogenética Óssea 2 , Proteínas Morfogenéticas Ósseas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , DNA/biossíntese , DNA/efeitos dos fármacos , Humanos , Ligamentos Longitudinais/efeitos dos fármacos , Ossificação do Ligamento Longitudinal Posterior/etiologia , Ossificação do Ligamento Longitudinal Posterior/patologia , Fragmentos de Peptídeos/biossíntese , Fragmentos de Peptídeos/efeitos dos fármacos , Pró-Colágeno/biossíntese , Pró-Colágeno/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Fatores de Crescimento Transformadores/farmacologia
8.
Calcif Tissue Int ; 56(2): 135-9, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7736322

RESUMO

We have examined the alkaline phosphatase (AP) activity of primary calvaria-derived osteoblast-like cells from the twy (tip-toe walking Yoshimura) and normal ICR control mouse. The twy mouse displays elevated osseous formation particularly in the spine, and the pathophysiological features resemble that of human ankylosing spinal hyperostosis. In the proliferative stage of cultured bone cells, parathyroid hormone (PTH) stimulation induced the elevation of AP activity of both twy and ICR mouse-derived cells. When they reached confluence, the AP activity of ICR mouse-derived cells ceased to increase with PTH stimulation. The twy mouse-derived cells, however, continued to respond to PTH, with the enzyme activity increasing even in the confluent, stationary stage. PTH stimulation also increased the intracellular cAMP content of twy mouse-derived cells but it did not influence that of ICR mouse-derived cells in the stationary stage. Moreover, stimulation with dibutyryl cAMP, but not with phorbol myristate acetate, increased the AP activity of both twy and ICR-derived bone cells irrespective of culture conditions, either in the proliferative or in the confluent stage. These data suggest that the protein kinase A-mediated pathway plays a pivotal role in bone cells with PTH stimulation, and that the uninhibited AP activity observed in twy mouse-derived bone cells might be due to some deviating process between the PTH ligand/receptor interaction and cAMP generation.


Assuntos
Fosfatase Alcalina/metabolismo , Hiperostose Esquelética Difusa Idiopática/enzimologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/enzimologia , Hormônio Paratireóideo/farmacologia , Animais , Divisão Celular , Células Cultivadas , AMP Cíclico/metabolismo , Modelos Animais de Doenças , Feminino , Hiperostose Esquelética Difusa Idiopática/genética , Hiperostose Esquelética Difusa Idiopática/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Camundongos Mutantes , Osteoblastos/patologia , Transdução de Sinais , Crânio/enzimologia , Crânio/patologia
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