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1.
Phys Rev Lett ; 127(3): 031102, 2021 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-34328784

RESUMEN

We report observations of gamma-ray emissions with energies in the 100-TeV energy region from the Cygnus region in our Galaxy. Two sources are significantly detected in the directions of the Cygnus OB1 and OB2 associations. Based on their positional coincidences, we associate one with a pulsar PSR J2032+4127 and the other mainly with a pulsar wind nebula PWN G75.2+0.1, with the pulsar moving away from its original birthplace situated around the centroid of the observed gamma-ray emission. This work would stimulate further studies of particle acceleration mechanisms at these gamma-ray sources.

2.
Phys Rev Lett ; 126(14): 141101, 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33891464

RESUMEN

We report, for the first time, the long-awaited detection of diffuse gamma rays with energies between 100 TeV and 1 PeV in the Galactic disk. Particularly, all gamma rays above 398 TeV are observed apart from known TeV gamma-ray sources and compatible with expectations from the hadronic emission scenario in which gamma rays originate from the decay of π^{0}'s produced through the interaction of protons with the interstellar medium in the Galaxy. This is strong evidence that cosmic rays are accelerated beyond PeV energies in our Galaxy and spread over the Galactic disk.

3.
Fa Yi Xue Za Zhi ; 37(4): 546-554, 2021 Aug.
Artículo en Zh | MEDLINE | ID: mdl-34726010

RESUMEN

ABSTRACT: In the field of forensic medicine, diagnosis of sudden cardiac death is limited by subjective factors and manual measurement methods, so some parameters may have estimation deviation or measurement deviation. As postmortem CT imaging plays a more and more important role in the appraisal of cause of death and cardiopathology research, the application of deep learning such as artificial intelligence technology to analyze vast amounts of cardiac imaging data has provided a possibility for forensic identification and scientific research workers to conduct precise diagnosis and quantitative analysis of cardiac diseases. This article summarizes the main researches on deep learning in the field of cardiac imaging in recent years, and proposes a feasible development direction for the application of deep learning in the virtual anatomy of sudden cardiac death at present.


Asunto(s)
Inteligencia Artificial , Aprendizaje Profundo , Autopsia , Muerte Súbita Cardíaca/etiología , Medicina Legal , Humanos
4.
J Transl Med ; 17(1): 173, 2019 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-31122242

RESUMEN

BACKGROUND: Prostate cancer is an extremely heterogeneous disease. Despite being clinically similar, some tumours are more likely to recur after surgery compared to others. Distinguishing those that need adjuvant or salvage radiotherapy will improve patient outcomes. The goal of this study was to identify circulating microRNA that could independently predict prostate cancer patient risk stratification after radical prostatectomy. METHODS: Seventy-eight prostate cancer patients were recruited at the Odette Cancer Centre in Sunnybrook Health Sciences Centre. All patients had previously undergone radical prostatectomy. Blood samples were collected simultaneously for PSA testing and miRNA analysis using NanoString nCounter technology. Of the 78 samples, 75 had acceptable miRNA quantity and quality. Patients were stratified into high- and low-risk categories based on Gleason score, pathological T stage, surgical margin status, and diagnostic PSA: patients with Gleason ≥ 8; pT3a and positive margin; pT3b and any margin; or diagnostic PSA > 20 µg/mL were classified as high-risk (n = 44) and all other patients were classified as low-risk (n = 31). RESULTS: Using our patient dataset, we identified a four-miRNA signature (miR-17, miR-20a, miR-20b, miR-106a) that can distinguish high- and low-risk patients, in addition to their pathological tumour stage. High expression of these miRNAs is associated with shorter time to biochemical recurrence in the TCGA dataset. These miRNAs confer an aggressive phenotype upon overexpression in vitro. CONCLUSIONS: This proof-of-principle report highlights the potential of circulating miRNAs to independently predict risk stratification of prostate cancer patients after radical prostatectomy.


Asunto(s)
Biomarcadores de Tumor/sangre , MicroARN Circulante/sangre , Prostatectomía , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/cirugía , Anciano , Línea Celular Tumoral , MicroARN Circulante/genética , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/genética
5.
Phys Rev Lett ; 123(5): 051101, 2019 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-31491288

RESUMEN

We report on the highest energy photons from the Crab Nebula observed by the Tibet air shower array with the underground water-Cherenkov-type muon detector array. Based on the criterion of a muon number measured in an air shower, we successfully suppress 99.92% of the cosmic-ray background events with energies E>100 TeV. As a result, we observed 24 photonlike events with E>100 TeV against 5.5 background events, which corresponds to a 5.6σ statistical significance. This is the first detection of photons with E>100 TeV from an astrophysical source.

6.
Phys Rev Lett ; 120(3): 031101, 2018 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-29400499

RESUMEN

We analyze the Sun's shadow observed with the Tibet-III air shower array and find that the shadow's center deviates northward (southward) from the optical solar disk center in the "away" ("toward") interplanetary magnetic field (IMF) sector. By comparing with numerical simulations based on the solar magnetic field model, we find that the average IMF strength in the away (toward) sector is 1.54±0.21_{stat}±0.20_{syst} (1.62±0.15_{stat}±0.22_{syst}) times larger than the model prediction. These demonstrate that the observed Sun's shadow is a useful tool for the quantitative evaluation of the average solar magnetic field.

13.
Genet Mol Res ; 14(4): 17739-48, 2015 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-26782419

RESUMEN

Grain shape and weight are the most important components of rice yield and are controlled by quantitative trait loci (QTLs). In this study, a double-haploid population, derived from the cross of japonica CJ06 and indica TN1, was used to analyze QTLs for grain shape and weight under two conditions: normal growth with unbroken husk and removing partial husk after flowering. Correlation analysis revealed that these traits, except grain weight, had a connection between the two conditions. Twenty-nine QTLs for grain shape and weight were detected on chromosomes 1 to 3; 6; 8 to 10; and 12, with the likelihood of odds value ranging from 2.38 to 5.36, including 10 different intervals. Some intervals were specifically detected after removing partial husk. The results contribute to the understanding of the genetic basis of grain filling and growth regulation, and provide us some assistance for improving grain plumpness in rice breeding.


Asunto(s)
Cruzamiento , Grano Comestible/genética , Oryza/genética , Sitios de Carácter Cuantitativo/genética , Mapeo Cromosómico , Cromosomas de las Plantas , Haploidia , Oryza/crecimiento & desarrollo , Fenotipo
17.
Phys Rev Lett ; 111(1): 011101, 2013 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-24027782

RESUMEN

We report on a clear solar-cycle variation of the Sun's shadow in the 10 TeV cosmic-ray flux observed by the Tibet air shower array during a full solar cycle from 1996 to 2009. In order to clarify the physical implications of the observed solar cycle variation, we develop numerical simulations of the Sun's shadow, using the potential field source surface model and the current sheet source surface (CSSS) model for the coronal magnetic field. We find that the intensity deficit in the simulated Sun's shadow is very sensitive to the coronal magnetic field structure, and the observed variation of the Sun's shadow is better reproduced by the CSSS model. This is the first successful attempt to evaluate the coronal magnetic field models by using the Sun's shadow observed in the TeV cosmic-ray flux.

18.
Genet Mol Res ; 12(4): 5623-33, 2013 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-24301931

RESUMEN

The genetic control of grain weight (GW) remains poorly understood. Quantitative trait loci (QTLs) determining the GW of rice were identified using a natural GW mutant, sgw. Using a segregating population derived from sgw (low GW) and cultivar 9311 ('9311'; indica, high GW), the chromosome segment associated with GW was detected on the short arm of chromosome 7. To validate and further refine the locus, QTL analysis based on F2 and F3 populations was conducted, and a single major QTL (designated as qsgw7) affecting the 1000-grain weight of paddy rice was identified on the short arm region of rice chromosome 7 between simple sequence repeat (SSR) markers RM21997 and RM22015, where 4 bacterial artificial chromosome clones, OJ1339_F05, P0506F02, P0011H09, and P0519E12, were present. Analysis of the near isogenic line for qsgw7 (NILqsgw7) showed that the grain length, width, and volume of paddy rice in NILqsgw7 were significantly lower than those in '9311' and that the 1000-grain weight, grain length, width, volume, and chalkiness of brown rice in NILqsgw7 were significantly lower than those in '9311'. These results suggested that the qsgw7 gene, which was identified in this study, may be a new GW-related QTL that could affect GW and grain shape, especially grain plumpness.


Asunto(s)
Oryza/genética , Sitios de Carácter Cuantitativo , Semillas/genética , Cromosomas de las Plantas/genética , Repeticiones de Microsatélite , Mutación , Oryza/crecimiento & desarrollo , Semillas/química , Semillas/crecimiento & desarrollo
20.
Eur Rev Med Pharmacol Sci ; 24(24): 12748-12756, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33378023

RESUMEN

OBJECTIVE: Long noncoding RNA (lncRNA) plays a vital role in the progression of various cancers. However, the potential mechanisms of NR2F1-AS1 in the tumorigenesis of neuroblastoma (NB) have not been determined. PATIENTS AND METHODS: The expression levels of NR2F1-AS1, miR-493 and TRIM2 were detected by RT-qPCR. The downstream target genes of NR2F1-AS1 or miR-493 were predicted by bioinformatics analysis (http://starbase.sysu.edu.cn/), which was further indicated by Luciferase reporter and RNA immunoprecipitation (RIP) assays. CCK-8, transwell, and TUNEL assays were performed to determine the viability, migration, invasion and apoptosis of NB cells. RESULTS: NR2F1-AS1 was highly expressed and miR-493 was lowly expressed in NB tissues and cell lines. The high expression of NR2F1-AS1 was associated with poor prognosis in NB. NR2F1-AS1 knockdown inhibited proliferation, migration, and invasion, and accelerated apoptosis of NB cells. MiR-493 was a downstream target of NR2F1-AS1, and the silencing of miR-493 reversed NR2F1-AS1 knockdown-attenuated progression of NB. Moreover, TRIM2 was demonstrated to be directly targeted by miR-493, and the upregulation of TRIM2 could abolish the inhibitory effect of miR-493 overexpression on the progression of NB. Finally, it was found that NR2F1-AS1 regulated TRIM2 expression by sponging miR-493. CONCLUSIONS: The present study demonstrated that NR2F1-AS1 promoted the progression of NB through the miR-493/TRIM2 axis. This finding may provide new insight into the treatment of NB.


Asunto(s)
MicroARNs/metabolismo , Neuroblastoma/metabolismo , ARN Largo no Codificante/metabolismo , Proteínas de Motivos Tripartitos/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Células Cultivadas , Humanos , MicroARNs/genética , Neuroblastoma/patología , ARN Largo no Codificante/genética , Proteínas de Motivos Tripartitos/genética , Ubiquitina-Proteína Ligasas/genética
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