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1.
J Virol ; : e0045824, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814067

RESUMO

Tryptophan metabolism plays a crucial role in facilitating various cellular processes essential for maintaining normal cellular function. Indoleamine 2,3-dioxygenase 1 (IDO1) catalyzes the conversion of tryptophan (Trp) into kynurenine (Kyn), thereby initiating the degradation of Trp. The resulting Kyn metabolites have been implicated in the modulation of immune responses. Currently, the role of IDO1-mediated tryptophan metabolism in the process of viral infection remains relatively unknown. In this study, we discovered that classical swine fever virus (CSFV) infection of PK-15 cells can induce the expression of IDO1, thereby promoting tryptophan metabolism. IDO1 can negatively regulate the NF-κB signaling by mediating tryptophan metabolism, thereby facilitating CSFV replication. We found that silencing the IDO1 gene enhances the expression of IFN-α, IFN-ß, and IL-6 by activating the NF-κB signaling pathway. Furthermore, our observations indicate that both silencing the IDO1 gene and administering exogenous tryptophan can inhibit CSFV replication by counteracting the cellular autophagy induced by Rapamycin. This study reveals a novel mechanism of IDO1-mediated tryptophan metabolism in CSFV infection, providing new insights and a theoretical basis for the treatment and control of CSFV.IMPORTANCEIt is well known that due to the widespread use of vaccines, the prevalence of classical swine fever (CSF) is shifting towards atypical and invisible infections. CSF can disrupt host metabolism, leading to persistent immune suppression in the host and causing significant harm when co-infected with other diseases. Changes in the host's metabolic profiles, such as increased catabolic metabolism of amino acids and the production of immunoregulatory metabolites and their derivatives, can also influence virus replication. Mammals utilize various pathways to modulate immune responses through amino acid utilization, including increased catabolic metabolism of amino acids and the production of immunoregulatory metabolites and their derivatives, thereby limiting viral replication. Therefore, this study proposes that targeting the modulation of tryptophan metabolism may represent an effective approach to control the progression of CSF.

2.
Nat Mater ; 22(4): 489-494, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36959503

RESUMO

Pressure-induced magnetic phase transitions are attracting interest as a means to detect superconducting behaviour at high pressures in diamond anvil cells, but determining the local magnetic properties of samples is a challenge due to the small volumes of sample chambers. Optically detected magnetic resonance of nitrogen vacancy centres in diamond has recently been used for the in situ detection of pressure-induced phase transitions. However, owing to their four orientation axes and temperature-dependent zero-field splitting, interpreting these optically detected magnetic resonance spectra remains challenging. Here we study the optical and spin properties of implanted silicon vacancy defects in 4H-silicon carbide that exhibit single-axis and temperature-independent zero-field splitting. Using this technique, we observe the magnetic phase transition of Nd2Fe14B at about 7 GPa and map the critical temperature-pressure phase diagram of the superconductor YBa2Cu3O6.6. These results highlight the potential of silicon vacancy-based quantum sensors for in situ magnetic detection at high pressures.

3.
Antonie Van Leeuwenhoek ; 117(1): 48, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429402

RESUMO

A gram-stain-positive, aerobic, rod-shaped bacterial strain capable of producing siderophores, named YIM B08730T, was isolated from a soil sample collected from Wumeng Mountain National Nature Reserve, Zhaotong City, Yunnan Province. Growth occurred at 10-45 °C (optimum, 35-40 â„ƒ), pH 7.0-9.0 (optimum, 7.0) and in the presence of 0-5 % (w/v) NaCl (optimum, 0-1 %, w/v). A comparative analysis of the 16S rRNA gene sequence (1558 bp) of strain YIM B08730T showed the highest similarity to Solibacillus isronensis JCM 13838T (96.2 %), followed by Solibacillus silvestris DSM 12223T (96.0 %) and Solibacillus kalamii ISSFR-015T (95.4 %). The main polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylserine and one unidentified lipid. The main respiratory quinone of strain YIM B08730T was menaquinone 7 (MK-7). The major fatty acids were iso-C15:0 and C16:1ω7c alcohol. The digital DNA-DNA hybridization and average nucleotide identity values between strain YIM B08730T and the reference strain S. isronensis JCM 13838T were 24.8 % and 81.2 %, respectively. The G + C content of the genomic DNA was 37.1 mol%. The genome of the novel strain contained genes associated with the production of siderophores, and it also revealed other functional gene clusters involved in plant growth promotion and soil bioremediation. Based on these phenotypic, chemotaxonomic and phylogenetic analyses, strain YIM B08730T is considered to be a novel species of the genus Solibacillus, for which the name Solibacillus ferritrahens sp. nov. is proposed. The type strain is YIM B08730T (= NBRC 116268T = CGMCC 1.60169T).


Assuntos
Bactérias , Fosfolipídeos , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , China , Bactérias/genética , Solo
4.
J Clin Ultrasound ; 52(2): 105-111, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37930057

RESUMO

OBJECTIVES: Ultrasound medical reports are an important means of diagnosing diseases and assessing treatment effectiveness. However, their professional terms and complex sentences often make it difficult for ordinary people to understand. Therefore, this study explores the clinical value of using artificial intelligence systems based on ChatGPT to interpret ultrasound medical reports. METHODS: In this study, a combination of online and offline questionnaires were used to survey both physicians and non-medical individuals. The questionnaires evaluated ChatGPT's interpretation of ultrasound reports from both professional and comprehensibility perspectives, and the results were analyzed using Excel spreadsheets. Additionally, a portion of the research content was evaluated using the Likert Scale 5-point method in the questionnaire. RESULTS: According to survey results, 67.4% of surveyed doctors believe that using ChatGPT for interpreting ultrasound medical reports can help improve work efficiency. At the same time, 69.72% of non-medical professionals believe it is necessary to enhance their understanding of medical ultrasound reports through ChatGPT interpretation, and 62.58% support the application of ChatGPT to ultrasound medical reports. The non-medical group's understanding of ultrasound medical reports significantly improved (p < 0.01) after implementing ChatGPT, However, 67.49% of the general public are concerned about ChatGPT's imperfect functionality, which may cause misleading information. This reflects that the public's trust in new technology is not high enough, and they are also worried about possible privacy leaks and security issues with ChatGPT technology. CONCLUSIONS: The higher acceptance and support of non-medical individuals for the interpretation of medical reports by ChatGPT might be due to the system's natural language processing abilities that allow them to better understand and evaluate report contents. However, the expertise and experience of physicians are still irreplaceable. This suggests that the ChatGPT-based ultrasound medical report interpretation system has certain clinical value and application prospects, but further optimization is necessary to address its shortcomings in data quality and professionalism. This study provides a reference and inspiration for promoting the application and development of ultrasound technology and artificial intelligence systems in the medical field.


Assuntos
Inteligência Artificial , Médicos , Humanos , Ultrassom , Confiabilidade dos Dados
5.
Opt Express ; 31(10): 15592-15598, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157657

RESUMO

Divacancy in silicon carbide has become an important solid-state system for quantum metrologies. To make it more beneficial for practical applications, we realize a fiber-coupled divacancy-based magnetometer and thermometer simultaneously. First, we realize an efficient coupling between the divacancy in a silicon carbide slice with a multimode fiber. Then the optimization of the power broadening in optically detected magnetic resonance (ODMR) of divacancy is performed to obtain a higher sensing sensitivity of 3.9 µT/Hz1/2. We then use it to detect the strength of an external magnetic field. Finally, we use the Ramsey methods to realize a temperature sensing with a sensitivity of 163.2 mK/Hz1/2. The experiments demonstrate that the compact fiber-coupled divacancy quantum sensor can be used for multiple practical quantum sensing.

6.
Opt Lett ; 48(6): 1423-1426, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36946943

RESUMO

Silicon vacancies in silicon carbide have drawn much attention for various types of quantum sensing. However, most previous experiments are realized using confocal scanning systems, which limits their practical applications. In this work, we demonstrate a compact fiber-integrated silicon carbide silicon-vacancy-based magnetometer at room temperature. First, we effectively couple the silicon vacancy in a tiny silicon carbide slice with an optical fiber tip and realize the readout of the spin signal through the fiber at the same time. We then study the optically detected magnetic resonance spectra at different laser and microwave powers, obtaining an optimized magnetic field sensitivity of 12.3 µT/Hz 12. Based on this, the magnetometer is used to measure the strength and polar angle of an external magnetic field. Through these experiments, we have paved the way for fiber-integrated silicon-vacancy-based magnetometer applications in practical environments, such as geophysics and biomedical sensing.

7.
Antonie Van Leeuwenhoek ; 116(6): 557-564, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37097385

RESUMO

A new Gram-negative, rod-shaped, flagellated bacterium was isolated from soil in the Guishan, Xinping County, Yuxi City, Yunnan Province, China, and named YIM B01952T. Growth occurred at 10-40 °C (optimum, 30 °C), pH 6.0-9.0 (optimum, pH 7.5) and with up to ≤ 5.0% (w/v) NaCl on Tryptic Soy Broth Agar (TSA) plates. Phylogenetic analysis based on the 16S rRNA gene and draft-genome sequence showed that strain YIM B01952T belonged to the genus Pseudomonas, and was closely related to the type strain of Pseudomonas alcaligenes (sequence similarity was 98.8%). The digital DNA-DNA hybridization (dDDH) value between strain YIM B01952T and the parallel strain P. alcaligenes ATCC 14909T was 49.0% based on the draft genome sequence. The predominant menaquinone was Q-9. The major fatty acids were summed feature 8 (C18:1 ω6c and/or C18:1 ω7c), summed feature 3 (C16:1 ω6c and/or C16:1 ω7c) and C16:0. The major polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, and phosphatidylglycerol. The genome size of strain YIM B01952T was 4.341 Mb, comprising 4156 predicted genes with a DNA G + C content of 66.4 mol%. In addition, we detected that strain YIM B01952T had some traditional functional genes (plant growth promotion and multidrug resistance), unique genes through genome comparison and analysis with similar strains. Based on genetic analyses and biochemical characterization, the strain YIM B01952T was identified as a novel species in the genus Pseudomonas, for which the name Pseudomonas subflava sp. nov. is proposed. The type strain is YIM B01952T (=CCTCC AB 2021498T = KCTC 92073T).


Assuntos
Ácidos Graxos , Pseudomonas , China , Filogenia , RNA Ribossômico 16S/genética , Pseudomonas/genética , DNA Bacteriano/genética , DNA Bacteriano/química , Ácidos Graxos/análise , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Fosfolipídeos/análise
8.
Curr Microbiol ; 80(7): 225, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37227525

RESUMO

In this study, a novel aerobic mesophilic bacterial strain with capable of degrading chitin, designated YIM B06366T, was isolated and classified. The rod-shaped, Gram-stain-negative, on-spore-forming bacterium originated from rhizosphere soil sample collected in Kunming City, Yunnan Province, southwest PR China. Strain YIM B06366T exhibited growth at temperatures between 20 and 35 °C (optimum, 30 °C) and at pH 6.0-8.0 (optimum, pH 6.0). The analysis of 16S rRNA gene sequence similarity revealed that strain YIM B06366T was most closely related to type strain Chitinolyticbacter meiyuanensis SYBC-H1T (98.9%). Phylogenetic analysis based on genome data indicated that strain YIM B06366T should be assigned to the genus Chitinolyticbacter. The Average Nucleotide Identity (ANI) and digital DNA-DNA Hybridization (dDDH) values between strain YIM B06366T and the reference strain Chitinolyticbacter meiyuanensis SYBC-H1T were 84.4% and 27.7%, respectively. The major fatty acids included Summed Feature 3 (C16:1 ω6c/C16:1 ω7c), Summed Feature 8 (C18:1 ω6c/C18:1 ω7c), and C16:0. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, aminophospholipids, and two unidentified phospholipids. The predominant menaquinone was Q-8, and the genomic DNA G + C content was 64.1%. Considering the polyphasic taxonomic evidence, strain YIM B06366T is proposed as a novel species within the genus Chitinolyticbacter, named Chitinolyticbacter albus sp. nov. (type strain YIM B06366T = KCTC 92434T = CCTCC AB 2022163T).


Assuntos
Quitina , Rizosfera , China , Filogenia , RNA Ribossômico 16S/genética , Madeira/química , Fosfolipídeos/química , Ácidos Graxos/química , DNA , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana
9.
Proc Natl Acad Sci U S A ; 117(24): 13374-13378, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32482874

RESUMO

Molecular hydrogen forms the archetypical quantum solid. Its quantum nature is revealed by behavior which is classically impossible and by very strong isotope effects. Isotope effects between [Formula: see text], [Formula: see text], and HD molecules come from mass difference and the different quantum exchange effects: fermionic [Formula: see text] molecules have antisymmetric wavefunctions, while bosonic [Formula: see text] molecules have symmetric wavefunctions, and HD molecules have no exchange symmetry. To investigate how the phase diagram depends on quantum-nuclear effects, we use high-pressure and low-temperature in situ Raman spectroscopy to map out the phase diagrams of [Formula: see text]-HD-[Formula: see text] with various isotope concentrations over a wide pressure-temperature (P-T) range. We find that mixtures of [Formula: see text], HD, and [Formula: see text] behave as an isotopic molecular alloy (ideal solution) and exhibit symmetry-breaking phase transitions between phases I and II and phase III. Surprisingly, all transitions occur at higher pressures for the alloys than either pure [Formula: see text] or [Formula: see text] This runs counter to any quantum effects based on isotope mass but can be explained by quantum trapping of high-kinetic energy states by the exchange interaction.

10.
Proc Natl Acad Sci U S A ; 117(16): 8736-8742, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32245813

RESUMO

We report here the pressure-induced amorphization and reversible structural transformation between two amorphous forms of SO2: molecular amorphous and polymeric amorphous, with the transition found at 26 GPa over a broad temperature regime, 77 K to 300 K. The transformation was observed by both Raman spectroscopy and X-ray diffraction in a diamond anvil cell. The results were corroborated by ab initio molecular dynamics simulations, where both forward and reverse transitions were detected, opening a window to detailed analysis of the respective local structures. The high-pressure polymeric amorphous form was found to consist mainly of disordered polymeric chains made of three-coordinated sulfur atoms connected via oxygen atoms, with few residual intact molecules. This study provides an example of polyamorphism in a system consisting of simple molecules with multiple bonds.

11.
Nano Lett ; 22(24): 9943-9950, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36507869

RESUMO

Spin defects in silicon carbide appear to be a promising tool for various quantum technologies, especially for quantum sensing. However, this technique has been used only at ambient pressure until now. Here, by combining this technique with diamond anvil cell, we systematically study the optical and spin properties of divacancy defects created at the surface of SiC at pressures up to 40 GPa. The zero-field-splitting of the divacancy spins increases linearly with pressure with a slope of 25.1 MHz/GPa, which is almost two-times larger than that of nitrogen-vacancy centers in diamond. The corresponding pressure sensing sensitivity is about 0.28 MPa/Hz-1/2. The coherent control of divacancy demonstrates that coherence time decreases as pressure increases. Based on these, the pressure-induced magnetic phase transition of Nd2Fe14B sample at high pressures was detected. These experiments pave the way to use divacancy in quantum technologies such as pressure sensing and magnetic detection at high pressures.

12.
Phys Rev Lett ; 126(1): 015702, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33480773

RESUMO

Mixtures of ammonia and water are major components of the "hot ice" mantle regions of icy planets. The ammonia-rich ammonia hemihydrate (AHH) plays a pivotal role as it precipitates from water-rich mixtures under pressure. It has been predicted to form ionic high-pressure structures, with fully disintegrated water molecules. Utilizing Raman spectroscopy measurements up to 123 GPa and first-principles calculations, we report the spontaneous ionization of AHH under compression. Spectroscopic measurements reveal that molecular AHH begins to transform into an ionic state at 26 GPa and then above ∼69 GPa transforms into the fully ionic P3[over ¯]m1 phase, AHH-III, characterized as ammonium oxide (NH_{4}^{+})_{2}O^{2-}.

13.
Radiology ; 287(2): 461-472, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29135366

RESUMO

Purpose To compare the benefits and harms of radiofrequency ablation (RFA) and hepatic resection (HR) and to test the consistency of currently available evidence. Materials and Methods PubMed, Embase, and the Cochrane Library were systematically searched for randomized controlled trials (RCTs) that compared the effects of HR and RFA for Barcelona Clinic Liver Cancer very early or early stage hepatocellular carcinoma (HCC). The primary outcome was overall survival, and secondary outcomes were recurrence rate, complication rate, and hospitalization duration. A random- or fixed-effects model according to the level of heterogeneity was applied. The meta-analysis was performed by using software, and trial sequential analysis (TSA) was performed. Results Five trials examining 742 patients were included in this study (sizes of trials: 161, 230, 168, 120, and 63 patients). The meta-analysis showed that RFA and HR had similar overall survival at 1 year (relative risk [RR], 1.39; 95% confidence interval [CI]: 0.36, 5.33; P = .63) and 3 years (RR, 1.40; 95% CI: 0.75, 2.62; P = .29), whereas RFA resulted in decreased overall survival compared with HR at 5 years (RR: 1.91; 95% CI: 1.32, 2.79; P = .001). The TSA showed that more trials were needed to control random errors. The incidence of overall recurrence was markedly higher and the hospitalization duration was significantly shorter in the RFA group than in the HR group, which was confirmed by TSA. Complications may have been less frequent in the RFA group, but TSA showed that additional trials were necessary to confirm this conclusion. Conclusion The indication for RFA as a primary treatment for patients who are eligible for HR with early stage HCC is unclear, and additional well-designed RCTs are needed. © RSNA, 2017 Online supplemental material is available for this article.


Assuntos
Carcinoma Hepatocelular/terapia , Ablação por Cateter , Hepatectomia , Neoplasias Hepáticas/terapia , Fígado/patologia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Ablação por Cateter/mortalidade , Hepatectomia/mortalidade , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida , Resultado do Tratamento
14.
Phys Rev Lett ; 119(6): 065301, 2017 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-28949614

RESUMO

In situ high-pressure low-temperature high-quality Raman data for hydrogen and deuterium demonstrate the presence of a novel phase, phase II^{'}, unique to deuterium and distinct from the known phase II. Phase II^{'} of D_{2} is not observed in hydrogen, making it the only phase that does not exist in both isotopes and occupies a significant part of P-T space from ∼25 to 110 GPa and below 125 K. For H_{2}, the data show that below 30 K the transition to phase II happens at as low as 73 GPa. The transformation from phase II to III commences at around ∼155 GPa and is completed by 170 GPa with the average pressure of ∼160 GPa being slightly higher than previously thought. The updated phase diagrams of H_{2} and D_{2} demonstrate the difference between the isotopes at low temperatures and moderate pressures, providing new information on the phase diagrams of both elements.

15.
Phys Rev Lett ; 122(19): 199602, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31144972
16.
Nanomaterials (Basel) ; 12(14)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35889698

RESUMO

As novel anodic materials for lithium-ion batteries (LIBs), transitional metal selenites can transform into metal oxide/selenide heterostructures in the first cycle, which helps to enhance the Li+ storage performance, especially in terms of high discharge capacity. Herein, well-defined hierarchical CoSeO3‧2H2O nanoflowers assembled using 10 nm-thick nanosheets are successfully synthesized via a facile one-step hydrothermal method. When used as anodic materials for LIBs, the CoSeO3‧2H2O nanoflowers exhibit a considerably high discharge capacity of 1064.1 mAh g-1 at a current density of 0.1 A g-1. In addition, the obtained anode possesses good rate capability and cycling stability. Owing to the superior electrochemical properties, the CoSeO3‧2H2O nanoflowers would serve as promising anodic materials for high-performance LIBs.

17.
J Phys Chem C Nanomater Interfaces ; 125(13): 7511-7517, 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-36158606

RESUMO

Our combined high-pressure synchrotron X-ray diffraction and Monte Carlo modeling studies show super-filling of the zeolite, and computational results suggest an occupancy by a maximum of nearly two inserted H2 molecules per framework unit, which is about twice that observed in gas hydrates. Super-filling prevents amorphization of the host material up to at least 60 GPa, which is a record pressure for zeolites and also for any group IV element being in full 4-fold coordination, except for carbon. We find that the inserted H2 forms an exotic topologically constrained glassy-like form, otherwise unattainable in pure hydrogen. Raman spectroscopy on confined H2 shows that the microporosity of the zeolite is retained over the entire investigated pressure range (up to 80 GPa) and that intermolecular interactions share common aspects with bulk hydrogen, while they are also affected by the zeolite framework.

18.
J Phys Chem Lett ; 12(30): 7229-7235, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34310154

RESUMO

Carbon disulfide is an archetypal double-bonded molecule belonging to the class of group IV-group VI, AB2 compounds. It is widely believed that, upon compression to several GPa at room temperature and above, a polymeric chain of type (-(C═S)-S-)n, named Bridgman's black polymer, will form. By combining optical spectroscopy and synchrotron X-ray diffraction data with ab initio simulations, we demonstrate that the structure of this polymer is different. Solid molecular CS2 polymerizes at ∼10-11 GPa. The polymer is disordered and consists of a mixture of 3-fold (C3) and 4-fold (C4) coordinated carbon atoms with some C═C double bonds. The C4/C3 ratio continuously increases upon further compression to 40 GPa. Upon decompression, structural changes are partially reverted, while the sample also undergoes partial disproportionation. Our work uncovers the nontrivial high-pressure structural evolution in one of the simplest molecular systems exhibiting molecular as well as polymeric phases.

19.
Eur J Radiol ; 129: 109050, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32447147

RESUMO

PURPOSE: To investigate the interobserver agreement of different thyroid imaging report and data system (TI-RADS) and ultrasound (US) features. METHODS: Two researchers independently searched PubMed, Embase and the Web of Science for relevant studies published between October 1972 and December 2018. Studies investigating interobserver agreement between different radiologists were included. The Guidelines for Reporting Reliability and Agreement Studies (GRRAS) and the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) score tools were applied to assess the quality of the studies. The data for the inter-agreements of TI-RADS categories and ultrasound features were extracted, and combined with STATA 12.0 (StataCorp, College Station, TX) was used. RESULTS: Seven studies including 927 patients were eligible for this meta-analysis. There was a moderate variability in the TI-RADS categories among radiologists (0.54; 95% CI: 0.49-0.58). Regarding the US features, the reliability of composition (0.61; 95% CI: 0.55-0.66) and calcification (0.71; 95% CI: 0.65-0.77) was good, the reliability of echogenicity (0.58; 95% CI: 0.51-0.64), shape (0.53; 95% CI: 0.45-0.62), margin (0.40; 95% CI: 0.32-0.48) and echogenic foci (0.43; 95% CI: 0.32-0.54) was moderate. Subgroup analyses showed that experience/training, the number of observers and the number of patients were the main factors influencing the variability. CONCLUSIONS: The interobserver agreement for the TI-RADS categories was moderate. There remains potential for improvement, especially in terms of the echogenicity, shape, margin and echogenic foci, the precision of the description and the targeted training needed.


Assuntos
Nódulo da Glândula Tireoide , Sistemas de Dados , Humanos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Ultrassonografia
20.
J Phys Chem Lett ; 11(16): 6626-6631, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32674573

RESUMO

Raman spectroscopy demonstrates that the rotational spectrum of solid hydrogen, and its isotope deuterium, undergoes profound transformations upon compression while still remaining in phase I. We show that these changes are associated with a loss of quantum character in the rotational modes and that the angular momentum J gradually ceases to be a good quantum rotational number. Through isotopic comparisons of the rotational Raman contributions, we reveal that hydrogen and deuterium evolve from a quantum rotor to a harmonic oscillator. We find that the mechanics behind this transformation can be well-described by a quantum-mechanical single inhibited rotor, accurately reproducing the striking spectroscopic changes observed in phase I.

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