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1.
Rev Sci Instrum ; 95(6)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38832851

RESUMEN

The widespread use of deep learning in processing point cloud data promotes the development of neural networks designed for point clouds. Point-based methods are increasingly becoming the mainstream in point cloud neural networks due to their high efficiency and performance. However, most of these methods struggle to balance both the geometric and semantic space of the point cloud, which usually leads to unclear local feature aggregation in geometric space and poor global feature extraction in semantic space. To address these two defects, we propose a bilateral feature fusion module capable of combining geometric and semantic data from the point cloud to enhance local feature extraction. In addition, we propose an offset vector attention module for better extraction of global features from point clouds. We provide specific ablation studies and visualizations in the article to validate our key modules. Experimental results show that the proposed method performs superior in both point cloud classification and segmentation tasks.

2.
Nanomaterials (Basel) ; 13(16)2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37630874

RESUMEN

Currently, heavy metal ion pollution in water is becoming more and more common, especially As (III), which is a serious threat to human health. In this experiment, a glassy carbon electrode modified with Fe3O4/MoS2 nanocomposites was used to select the square wave voltammetry (SWV) electrochemical detection method for the detection of trace As (III) in water. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) showed that Fe3O4 nanoparticles were uniformly attached to the surface of MoS2 and were not easily agglomerated. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) showed that Fe3O4/MoS2 has higher sensitivity and conductivity. After optimizing the experimental conditions, the Fe3O4/MoS2-modified glassy carbon electrode exhibited high sensitivity (3.67 µA/ppb) and a low detection limit (0.70 ppb), as well as excellent interference resistance and stability for As (III).

3.
Nanomaterials (Basel) ; 12(5)2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35269271

RESUMEN

Arsenic is extremely abundant in the Earth's crust and is one of the most common environmental pollutants in nature. In the natural water environment and surface soil, arsenic exists mainly in the form of trivalent arsenite (As(III)) and pentavalent arsenate (As(V)) ions, and its toxicity can be a serious threat to human health. In order to manage the increasingly serious arsenic pollution in the living environment and maintain a healthy and beautiful ecosystem for human beings, it is urgent to conduct research on an efficient sensing method suitable for the detection of As(III) ions. Electrochemical sensing has the advantages of simple instrumentation, high sensitivity, good selectivity, portability, and the ability to be analyzed on site. This paper reviews various electrode systems developed in recent years based on nanomaterials such as noble metals, bimetals, other metals and their compounds, carbon nano, and biomolecules, with a focus on electrodes modified with noble metal and metal compound nanomaterials, and evaluates their performance for the detection of arsenic. They have great potential for achieving the rapid detection of arsenic due to their excellent sensitivity and strong interference immunity. In addition, this paper discusses the relatively rare application of silicon and its compounds as well as novel polymers in achieving arsenic detection, which provides new ideas for investigating novel nanomaterial sensing. We hope that this review will further advance the research progress of high-performance arsenic sensors based on novel nanomaterials.

4.
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.

5.
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.

6.
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.

7.
Zhonghua Nan Ke Xue ; 24(8): 675-680, 2018 Aug.
Artículo en Chino | MEDLINE | ID: mdl-30173423

RESUMEN

Priapism is a rare pathological penile erection, and there are some inadequacies in its definition, classification, diagnosis, and therapeutic strategies. In this article, we sum up our years of experience with priapism and put forward some new views and ideas about its definition, classification, pathophysiologic process, pathological change, diagnostic essentials, therapeutic measures, indications of successful treatment, and post-therapeutic rehabilitation of erectile function. We also describe the clinical features, diagnosis and treatment of some special types of priapism, such as intermittent seizure, sleep-related painful erection, and tumor-related priapism, hoping to help urologists and andrologists in the further understanding and management of priapism.


Asunto(s)
Erección Peniana , Priapismo , Humanos , Masculino , Priapismo/clasificación , Priapismo/diagnóstico , Priapismo/etiología , Priapismo/terapia
8.
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.

9.
J Altern Complement Med ; 24(5): 481-485, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29406821

RESUMEN

PURPOSE: This study is aimed to explore the combined use of goiter dispersion formula and antithyroid drugs in the treatment of patients with neurologic manifestations of Graves' disease by examining its modulating effects on patients' cytokines. METHODS: A total of 80 patients with Graves' disease were randomly divided into treatment and control groups. Patients of the treatment group received goiter dispersion formula and antithyroid drugs (methimazole or propylthiouracil), whereas those of the control group received antithyroid drug alone. FT3, FT4, and TSH contents were detected by chemiluminescence immunoassay at pre- and post-treatment; interleukin (IL)-2, IL-8, and IL-17 serum levels before and after the treatment were detected by radioimmunoassay; thyroid B-mode ultrasound and liver and renal function tests were performed in all patients of both groups. An additional cohort of 40 healthy subjects was recruited for baseline measurement. RESULTS: All the enrolled patients completed the trial. The effective treatment rate was higher in the treatment group than in the control group, of which the difference was statistically significant (treatment group, 95%; control group, 75%, p < 0.01). For blood cytokine, before treatment, IL-2 was reduced whereas IL-8 and IL-17 were increased significantly in both groups of patients with Graves' disease comparing with those in healthy subjects (p < 0.01). For patients of the treatment group, after treatment, their IL-2 levels were increased (p < 0.01) with concomitant decreases in IL-8 and IL-17 levels (p < 0.05). There were no significant changes in blood cytokine levels before and after treatment in the control group. CONCLUSIONS: Goiter dispersion formula significantly improved the treatment outcomes of antithyroid drug in hyperthyroidism patients with neurologic manifestations of Graves' disease by modulating IL-2, IL-8, and IL-17. The data supported the rationale for the use of goiter dispersion formula in Graves' disease treatment.


Asunto(s)
Citocinas/sangre , Medicamentos Herbarios Chinos/uso terapéutico , Enfermedad de Graves/complicaciones , Enfermedad de Graves/fisiopatología , Hipertiroidismo/complicaciones , Hipertiroidismo/tratamiento farmacológico , Adulto , Anciano , Femenino , Humanos , Hipertiroidismo/sangre , Masculino , Medicina Tradicional China , Persona de Mediana Edad , Adulto Joven
10.
Virol Sin ; 32(2): 130-138, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28466442

RESUMEN

Recent studies have declared that members of the ssDNA virus family Microviridae play an important role in multiple environments, as they have been found taking a dominant position in the human gut. The aim of this study was to analyze the overall composition of the gut virome in coronary heart disease (CHD) patients, and try to discover the potential link between the human gut virome and CHD. Viral metagenomics methods were performed to detect the viral sequences in fecal samples collected from CHD inpatients and healthy persons as controls. We present the analysis of the virome composition in these CHD patients and controls. Our data shows that the virome composition may be linked to daily living habits and the medical therapy of CHD. Virgaviridae and Microviridae were the two dominant types of viruses found in the enteric virome of CHD patients. Fourteen divergent viruses belonging to the family Microviridae were found, twelve of which were grouped into the subfamily Gokushovirinae, while the remaining two strains might represent two new subfamilies within Microviridae, according to the phylogenetic analysis. In addition, the genomic organization of these viruses has been characterized.


Asunto(s)
Biodiversidad , Enfermedad Coronaria/virología , Heces/virología , Virus/clasificación , Virus/genética , Anciano , Anciano de 80 o más Años , Humanos , Metagenómica , Persona de Mediana Edad
11.
Biomed Res Int ; 2017: 3796359, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28497047

RESUMEN

Objectives. We aimed to explore the impact of gut microbiota in coronary heart disease (CHD) patients through high-throughput sequencing. Methods. A total of 29 CHD in-hospital patients and 35 healthy volunteers as controls were included. Nucleic acids were extracted from fecal samples, followed by α diversity and principal coordinate analysis (PCoA). Based on unweighted UniFrac distance matrices, unweighted-pair group method with arithmetic mean (UPGMA) trees were created. Results. After data optimization, an average of 121312 ± 19293 reads in CHD patients and 234372 ± 108725 reads in controls was obtained. Reads corresponding to 38 phyla, 90 classes, and 584 genera were detected in CHD patients, whereas 40 phyla, 99 classes, and 775 genera were detected in controls. The proportion of phylum Bacteroidetes (56.12%) was lower and that of phylum Firmicutes was higher (37.06%) in CHD patients than those in the controls (60.92% and 32.06%, P < 0.05). PCoA and UPGMA tree analysis showed that there were significant differences of gut microbial compositions between the two groups. Conclusion. The diversity and compositions of gut flora were different between CHD patients and healthy controls. The incidence of CHD might be associated with the alteration of gut microbiota.


Asunto(s)
Bacterias , Enfermedad Coronaria/microbiología , Microbioma Gastrointestinal/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Anciano , Anciano de 80 o más Años , Bacterias/clasificación , Bacterias/genética , Enfermedad Coronaria/epidemiología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad
12.
Zhonghua Nan Ke Xue ; 22(4): 330-4, 2016 Apr.
Artículo en Chino | MEDLINE | ID: mdl-30088410

RESUMEN

Objective: To investigate the pathogenesis and management of sleep-related painful erections(SRPE). Methods: This study included 9 SRPE patients aged 39- 59( mean 47. 8) years and with a mean disease course of 13. 5 ± 1. 2 months. We conducted blood urine routine examinations, collected four blood coagulation indexes, obtained IIEF-5 scores and sexual hormone levels, and recorded the nocturnal penile tumescence( NPT) and results of polysomnographic sleep monitoring of the patients. After 1,4,8,12,and 24 weeks of individualized treatment for each patient, we performed telephone follow-up for therapeutic effects and adverse drug reactions. Results: All the 9 patients were diagnosed with primary SRPE after excluding other diseases,6 of them treated with chlorimipramine or chlorimipramine combined with other medicine and the other 3 by antiandrogen therapy. Complete pain remission was achieved by 77. 78% at 4 weeks and 66. 67% at 24 weeks. The 3 patients treated by antiandrogen therapy experienced recurrence at 24 weeks but relieved after 1 week of adjusted treatment. Conclusion: Chlorimipramine, combination of chlorimipramine with medicine, and antiandrogen therapy are all evidently effective for the treatment of primary SRPE.


Asunto(s)
Dolor , Erección Peniana , Parasomnias del Sueño REM/diagnóstico , Parasomnias del Sueño REM/tratamiento farmacológico , Adulto , Humanos , Masculino , Persona de Mediana Edad
13.
Int J Clin Exp Pathol ; 8(10): 13374-80, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26722543

RESUMEN

The receptor tyrosine kinase of EphA2 has been shown frequently overexpressed in various types of human carcinomas, which implicated that it plays important roles in carcinogenesis. Although EphA2 protein expression has been investigated in many types of human carcinomas, the relationship between the expression of EphA2 protein in clear cell renal cell carcinoma was not well documented. In the present study, using specific anit-EphA2 polyclonal antibody and immunohistochemistry, we evaluated EphA2 protein expression levels in clear cell RCC specimens surgically resected from 90 patients. Our results shows that EphA2 protein was positively expressed in all normal renal tubes of 90 samples (100%, 3+), which was expressed at low levels in renal cortex but high levels in the collecting ducts of the renal medulla and papilla. EphA2 was negatively or weakly expressed in 30 out of 90 samples (33.3%, 0/1+), moderately expressed in 24 samples (26.7%, 2+) and strongly expressed in 36 samples (40%, 3+). Expression of EphA2 was positively associated with age (P=0.029), tumor diameters (P<0.001) and Fuhrman nuclear grade (P<0.001). Our results indicate that EphA2 variably expressed in clear cell renal cell carcinomas. High expression of EphA2 was more often found in big size and high nuclear grade tumors, which indicated EphA2 protein may be used as a new marker for the prognosis of clear cell renal cell carcinoma.


Asunto(s)
Biomarcadores de Tumor/análisis , Carcinoma de Células Renales/patología , Neoplasias Renales/patología , Receptor EphA2/biosíntesis , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Renales/metabolismo , Femenino , Humanos , Inmunohistoquímica , Neoplasias Renales/metabolismo , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Receptor EphA2/análisis
14.
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.

15.
Science ; 314(5798): 439-43, 2006 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-17053141

RESUMEN

The intensity of Galactic cosmic rays is nearly isotropic because of the influence of magnetic fields in the Milky Way. Here, we present two-dimensional high-precision anisotropy measurement for energies from a few to several hundred teraelectronvolts (TeV), using the large data sample of the Tibet Air Shower Arrays. Besides revealing finer details of the known anisotropies, a new component of Galactic cosmic ray anisotropy in sidereal time is uncovered around the Cygnus region direction. For cosmic-ray energies up to a few hundred TeV, all components of anisotropies fade away, showing a corotation of Galactic cosmic rays with the local Galactic magnetic environment. These results have broad implications for a comprehensive understanding of cosmic rays, supernovae, magnetic fields, and heliospheric and Galactic dynamic environments.

16.
Phys Rev Lett ; 93(6): 061101, 2004 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-15323615

RESUMEN

We report on the solar diurnal variation of the galactic cosmic-ray intensity observed by the Tibet III air shower array during the period from 1999 to 2003. In the higher-energy event samples (12 and 6.2 TeV), the variations are fairly consistent with the Compton-Getting anisotropy due to the terrestrial orbital motion around the Sun, while the variation in the lower-energy event sample (4.0 TeV) is inconsistent with this anisotropy. This suggests an additional anisotropy superposed at the multi-TeV energies, e.g., the solar modulation effect. This is the highest-precision measurement of the Compton-Getting anisotropy ever made.

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