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2.
Nat Commun ; 14(1): 7396, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37978297

RESUMEN

Antiferromagnetic (AF) topological materials offer a fertile ground to explore a variety of quantum phenomena such as axion magnetoelectric dynamics and chiral Majorana fermions. To realize such intriguing states, it is essential to establish a direct link between electronic states and topology in the AF phase, whereas this has been challenging because of the lack of a suitable materials platform. Here we report the experimental realization of the AF topological-insulator phase in NdBi. By using micro-focused angle-resolved photoemission spectroscopy, we discovered contrasting surface electronic states for two types of AF domains; the surface having the out-of-plane component in the AF-ordering vector displays Dirac-cone states with a gigantic energy gap, whereas the surface parallel to the AF-ordering vector hosts gapless Dirac states despite the time-reversal-symmetry breaking. The present results establish an essential role of combined symmetry to protect massless Dirac fermions under the presence of AF order and widen opportunities to realize exotic phenomena utilizing AF topological materials.

3.
Phys Rev E ; 107(6-2): 065208, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37464686

RESUMEN

We show that an ultra-high-pressure plasma can be generated when an aligned nanowire is irradiated by a laser with relativistic transparent intensity. Using a particle-in-cell simulation, we demonstrate that the expanded plasma following the z pinch becomes relativistically transparent and compressed longitudinally by the oscillating component of the ponderomotive force. The compressed structure persists throughout the pulse duration with a maximum pressure of 40Tbar when irradiated with a laser at an intensity of 10^{23}Wcm^{-2}, 5× higher than the z-pinch pressure. These results suggest an alternative approach to extending the current attainable pressure in the laboratory.

4.
J Med Case Rep ; 17(1): 186, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37101309

RESUMEN

BACKGROUND: Chromosome 5p partial monosomy (5p-syndrome) and chromosome 6p partial trisomy are chromosomal abnormalities that result in a variety of symptoms, but liver dysfunction is not normally one of them. Alagille syndrome (OMIM #118450) is a multisystem disorder that is defined clinically by hepatic bile duct paucity and cholestasis, in association with cardiac, skeletal, and ophthalmologic manifestations, and characteristic facial features. Alagille syndrome is caused by mutations in JAG1 on chromosome 20 or NOTCH2 on chromosome 1. Here, we report a preterm infant with karyotype 46,XX,der(5)t(5,6)(p15.2;p22.3) and hepatic dysfunction, who was diagnosed as having incomplete Alagille syndrome. CASE PRESENTATION: The Japanese infant was diagnosed based on the cardiac abnormalities, ocular abnormalities, characteristic facial features, and liver pathological findings. Analysis of the JAG1 and NOTCH sequences failed to detect any mutations in these genes. CONCLUSIONS: These results suggest that, besides the genes that are known to be responsible for Alagille syndrome, other genetic mutations also may cause Alagille syndrome.


Asunto(s)
Síndrome de Alagille , Lactante , Humanos , Recién Nacido , Síndrome de Alagille/diagnóstico , Síndrome de Alagille/genética , Síndrome de Alagille/patología , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Recien Nacido Prematuro , Cariotipo
5.
Nature ; 617(7961): 493-498, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36889355

RESUMEN

Photocathodes-materials that convert photons into electrons through a phenomenon known as the photoelectric effect-are important for many modern technologies that rely on light detection or electron-beam generation1-3. However, current photocathodes are based on conventional metals and semiconductors that were mostly discovered six decades ago with sound theoretical underpinnings4,5. Progress in this field has been limited to refinements in photocathode performance based on sophisticated materials engineering1,6. Here we report unusual photoemission properties of the reconstructed surface of single crystals of the perovskite oxide SrTiO3(100), which were prepared by simple vacuum annealing. These properties are different from the existing theoretical descriptions4,7-10. In contrast to other photocathodes with a positive electron affinity, our SrTiO3 surface produces, at room temperature, discrete secondary photoemission spectra, which are characteristic of efficient photocathode materials with a negative electron affinity11,12. At low temperatures, the photoemission peak intensity is enhanced substantially and the electron beam obtained from non-threshold excitations shows longitudinal and transverse coherence that differs from previous results by at least an order of magnitude6,13,14. The observed emergence of coherence in secondary photoemission points to the development of a previously undescribed underlying process in addition to those of the current theoretical photoemission framework. SrTiO3 is an example of a fundamentally new class of photocathode quantum materials that could be used for applications that require intense coherent electron beams, without the need for monochromatic excitations.

7.
Public Health ; 216: 39-44, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36791649

RESUMEN

OBJECTIVE: The aim of this study was to investigate the epidemiology of post-COVID conditions beyond 12 months and identify factors associated with the persistence of each condition. STUDY DESIGN: This was a cross-sectional questionnaire-based survey. METHODS: We conducted the survey among patients who had recovered from COVID-19 and visited our institute between February 2020 and November 2021. Demographic and clinical data and data regarding the presence and duration of post-COVID conditions were obtained. We identified factors associated with the persistence of post-COVID conditions using multivariable linear regression analyses. RESULTS: Of 1148 surveyed patients, 502 completed the survey (response rate, 43.7%). Of these, 393 patients (86.4%) had mild disease in the acute phase. The proportion of participants with at least one symptom at 6, 12, 18, and 24 months after symptom onset or COVID-19 diagnosis was 32.3% (124/384), 30.5% (71/233), 25.8% (24/93), and 33.3% (2/6), respectively. The observed associations were as follows: fatigue persistence with moderate or severe COVID-19 (ß = 0.53, 95% confidence interval [CI] = 0.06-0.99); shortness of breath with moderate or severe COVID-19 (ß = 1.39, 95% CI = 0.91-1.87); cough with moderate or severe COVID-19 (ß = 0.84, 95% CI = 0.40-1.29); dysosmia with being female (ß = -0.57, 95% CI = -0.97 to -0.18) and absence of underlying medical conditions (ß = -0.43, 95% CI = -0.82 to -0.05); hair loss with being female (ß = -0.61, 95% CI = -1.00 to -0.22), absence of underlying medical conditions (ß = -0.42, 95% CI = -0.80 to 0.04), and moderate or severe COVID-19 (ß = 0.97, 95% CI = 0.41-1.54); depressed mood with younger age (ß = -0.02, 95% CI = -0.04 to -0.004); and loss of concentration with being female (ß = -0.51, 95% CI = -0.94 to -0.09). CONCLUSIONS: More than one-fourth of patients after recovery from COVID-19, most of whom had had mild disease in the acute phase, had at least one symptom at 6, 12, 18, and 24 months after onset of COVID-19, indicating that not a few patients with COVID-19 suffer from long-term residual symptoms, even in mild cases.


Asunto(s)
COVID-19 , Humanos , Femenino , Masculino , Síndrome Post Agudo de COVID-19 , Prueba de COVID-19 , Estudios Transversales , Tos
8.
Rev Sci Instrum ; 93(11): 113535, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36461436

RESUMEN

Measuring the time variation of the wavenumber spectrum of turbulence is important for understanding the characteristics of high-temperature plasmas, and the application of a Doppler reflectometer with simultaneous multi-frequency sources is expected. To implement this diagnostic in future fusion devices, the use of a phased array antenna (PAA) that can scan microwave beams without moving antennas is recommended. Since the frequency-scanning waveguide leaky-wave antenna-type PAA has a complex structure, we have investigated its characteristics by modeling it with 3D metal powder additive manufacturing (AM). First, a single waveguide is fabricated to understand the characteristics of 3D AM techniques, and it is clear that there are differences in performance depending on the direction of manufacture and surface treatment. Then, a PAA is made, and it is confirmed that the beam can be emitted in any direction by frequency scanning. The plasma flow velocity can be measured by applying the 3D manufacturing PAA to plasma measurement.

9.
Rev Sci Instrum ; 93(11): 113518, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36461466

RESUMEN

Doppler-backscattering (DBS) has been used in several fusion plasma devices because it can measure the perpendicular velocity of electron density perturbation v⊥, the radial electric field Er, and the perpendicular wavenumber spectrum S(k⊥) with high wavenumber and spatial resolution. In particular, recently constructed frequency comb DBS systems enable observation of turbulent phenomena at multiple observation points in the radial direction. A dual-comb microwave DBS system has been developed for the large helical device plasma measurement. Since it is desirable to control the gain of each frequency-comb separately, a frequency-comb DBS system was developed with a function to adjust the gain of the scattered signal intensity of each channel separately. A correction processing method was also developed to correct the amplitude ratio and the phase difference between the in-phase and quadrature-phase signals of the scattered signals. As a result, the error in Doppler-shift estimation required to observe vertical velocity and the radial electric field was reduced, which enables more precise measurements.

10.
Public Health ; 213: 71-77, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36395682

RESUMEN

OBJECTIVES: Most research on the association between parental or family socio-economic status and psychological adjustment in children has been performed mainly in Western countries, while there is limited evidence of such research in Asian countries. We examined the association of parental occupation and educational levels and household income with children's psychological adjustment in Japan. STUDY DESIGN: This was a cross-sectional study. METHODS: Study subjects were 6329 children aged 3 years. Children's psychological adjustment was assessed using the Strengths and Difficulties Questionnaire. RESULTS: Compared with having an unemployed father, having a father who worked in an administrative and managerial or clerical job was associated with a lower prevalence of peer problems. Compared with having an unemployed mother, having a mother who worked in the professional and engineering, sales, service, or manufacturing process area was associated with a lower prevalence of low prosocial behaviors, whereas having a mother who worked in the clerical, service, or manufacturing process area was associated with an increased prevalence of emotional problems. Having a mother who worked in a clerical area was associated with a higher prevalence of conduct problems. Higher paternal and maternal educational levels were inversely associated with the prevalence of conduct problems and hyperactivity but were positively associated with low prosocial behaviors. A higher household income was inversely associated with the prevalence of emotional problems, conduct problems, and hyperactivity. CONCLUSION: Parental occupation, educational levels, and household income may affect children's psychological adjustment in Japan.


Asunto(s)
Ajuste Emocional , Madres , Niño , Femenino , Humanos , Estudios Transversales , Japón/epidemiología , Escolaridad
11.
Sci Rep ; 12(1): 16818, 2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-36207383

RESUMEN

Bright, energetic, and directional electron bunches are generated through efficient energy transfer of relativistic intense (~ 1019 W/cm2), 30 femtosecond, 800 nm high contrast laser pulses to grating targets (500 lines/mm and 1000 lines/mm), under surface plasmon resonance (SPR) conditions. Bi-directional relativistic electron bunches (at 40° and 150°) are observed exiting from the 500 lines/mm grating target at the SPR conditions. The surface plasmon excited grating target enhances the electron flux and temperature by factor of 6.0 and 3.6, respectively, compared to that of the plane substrate. Particle-in-Cell simulations indicate that fast electrons are emitted in different directions at different stages of the laser interaction, which are related to the resultant surface magnetic field evolution. This study suggests that the SPR mechanism can be used to generate multiple, bright, ultrafast relativistic electron bunches for a variety of applications.

12.
J Prev Alzheimers Dis ; 9(4): 752-757, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36281680

RESUMEN

BACKGROUND: There is growing interest in examining objective markers for early identification and behavioral intervention to prevent dementia and mild cognitive impairment in clinical and community settings. OBJECTIVE: To investigate the association between salivary alpha-amylase as an objective measure of psychological stress response and mild cognitive impairment for the implication of psychological stress in the development of mild cognitive impairment. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study involved 865 participants aged ≥ 65 years. A saliva sample was collected in the morning, and the levels of salivary alpha-amylase were assayed. Mild cognitive impairment was evaluated using the Japanese version of the Montreal Cognitive Assessment; a score < 26 was indicative of mild cognitive impairment. A multivariable logistic regression model was used to examine the association of salivary alpha-amylase and mild cognitive impairment after adjusting for age, sex, current drinking status, current smoking status, body mass index, hypertension, diabetes mellitus, physical activity, education, social support, social network, and heart rate variability. RESULTS: Salivary alpha-amylase was associated with mild cognitive impairment (the multivariable-adjusted odds ratio [95% confidence interval] for the 1-standard deviation increment of log-transformed salivary alpha-amylase was 1.24 [1.07-1.44]). This significant association persisted after adjusting for various confounding factors. CONCLUSION: Elevation of salivary alpha-amylase was associated with mild cognitive impairment among Japanese community-dwelling older adults. This suggests that salivary alpha-amylase is a useful objective marker of psychological stress responses associated with mild cognitive impairment.


Asunto(s)
Disfunción Cognitiva , alfa-Amilasas Salivales , Humanos , Anciano , Estudios Transversales , Japón , Pruebas de Estado Mental y Demencia , Biomarcadores
13.
J Infect Chemother ; 28(11): 1546-1551, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35963600

RESUMEN

OBJECTIVES: To investigate the prevalence of post coronavirus disease (COVID-19) condition of the Omicron variant in comparison to other strains. STUDY DESIGN: A single-center cross-sectional study. METHODS: Patients who recovered from Omicron COVID-19 infection (Omicron group) were interviewed via telephone, and patients infected with other strains (control group) were surveyed via a self-reporting questionnaire. Data on patients' characteristics, information regarding the acute-phase COVID-19, as well as presence and duration of COVID-19-related symptoms were obtained. Post COVID-19 condition in this study was defined as a symptom that lasted for at least 2 months, within 3 months of COVID-19 onset. We investigated and compared the prevalence of post COVID-19 condition in both groups after performing propensity score matching. RESULTS: We conducted interviews for 53 out of 128 patients with Omicron and obtained 502 responses in the control group. After matching cases with controls, 18 patients from both groups had improved covariate balance of the factors: older adult, female sex, obesity, and vaccination status. There were no significant differences in the prevalence of each post COVID-19 condition between the two groups. The number of patients with at least one post COVID-19 condition in the Omicron and control groups were 1 (5.6%) and 10 (55.6%) (p = 0.003), respectively. CONCLUSIONS: The prevalence of post Omicron COVID-19 conditions was less than that of the other strains. Further research with a larger sample size is needed to investigate the precise epidemiology of post COVID-19 condition of Omicron, and its impact on health-related quality of life and social productivity.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anciano , COVID-19/epidemiología , Estudios Transversales , Femenino , Humanos , Calidad de Vida
14.
AJNR Am J Neuroradiol ; 43(8): 1124-1130, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35835591

RESUMEN

BACKGROUND AND PURPOSE: ICA-selective MRA using a pencil beam presaturation pulse can accurately visualize anterior communicating artery flow. We evaluated the impact of anterior communicating artery flow on the perioperative hemodynamic status and new ischemic lesions after carotid revascularization. MATERIALS AND METHODS: Eighty-three patients with carotid artery stenosis were included. We assessed anterior communicating artery flow using ICA-selective MRA. The preoperative hemodynamic status was measured using SPECT. We also measured the change in regional cerebral oxygen saturation after temporary ICA occlusion. New ischemic lesions were evaluated by DWI on the day after treatment. RESULTS: Anterior communicating artery flow was detected in 61 patients, but it was not detected in 22 patients. Preoperative cerebrovascular reactivity was significantly higher in patients with (versus without) anterior communicating artery flow with a mean peak systolic velocity of ≥200 cm/s (39.6% [SD, 23.8%] versus 25.2% [SD, 16.4%]; P = .030). The decrease in mean regional cerebral oxygen saturation was significantly greater in patients without (versus with) anterior communicating artery flow (8.5% [SD, 5.6%] versus 3.7% [SD, 3.8%]; P = .002). New ischemic lesions after the procedure were observed in 23 patients. The multivariate logistic regression analysis revealed that anterior communicating artery flow (OR, 0.07; 95% CI, 0.012-0.45; P = .005) was associated with new ischemic lesions. CONCLUSIONS: The absence of anterior communicating artery flow influenced the perioperative hemodynamic status in patients with carotid stenosis and was associated with an increased incidence of new ischemic lesions after carotid revascularization.


Asunto(s)
Arteria Carótida Interna , Estenosis Carotídea , Humanos , Arteria Carótida Interna/patología , Arterias Carótidas , Imagen por Resonancia Magnética , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/cirugía , Estenosis Carotídea/patología , Arteria Cerebral Anterior , Circulación Cerebrovascular
16.
Phys Rev Lett ; 128(12): 125001, 2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35394307

RESUMEN

Turbulence spreading into the edge stochastic magnetic layer induced by magnetic fluctuation is observed at the sharp boundary region in the large helical device. The density fluctuation excited at the sharp boundary region with a large pressure gradient does not propagate into the boundary region due to the blocking of turbulence spreading by the large second derivative of the pressure gradient. Once the magnetic fluctuation appears at the boundary, the density fluctuation begins to penetrate the edge stochastic layer and the second derivative of the pressure gradient also decreases. The increase of density fluctuation in this layer results in the broadening and reduction of the peak divertor heat load. It is demonstrated that magnetic fluctuation plays a key role in controlling the turbulence spreading at the boundary of plasma which contributes to the reduction of divertor heat load.

17.
Phys Rev Lett ; 128(12): 127401, 2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35394320

RESUMEN

Competition and cooperation among orders is at the heart of many-body physics in strongly correlated materials and leads to their rich physical properties. It is crucial to investigate what impact many-body physics has on extreme nonlinear optical phenomena, with the possibility of controlling material properties by light. However, the effect of competing orders and electron-electron correlations on highly nonlinear optical phenomena has not yet been experimentally clarified. Here, we investigated high-order harmonic generation from the Mott-insulating phase of Ca_{2}RuO_{4}. Changing the gap energy in Ca_{2}RuO_{4} as a function of temperature, we observed a strong enhancement of high order harmonic generation at 50 K, increasing up to several hundred times compared to room temperature. We discovered that this enhancement can be well reproduced by an empirical scaling law that depends only on the material gap energy and photon emission energy. Such a scaling law can hardly be explained by the electronic structure change in the single particle model and has not been predicted by previous theoretical studies on HHG in the simple Mott-Hubbard model. Our results suggest that the highly nonlinear optical response of strongly correlated materials is influenced by competition among the multiple degrees of freedom and electron-electron correlations.

19.
Sci Rep ; 12(1): 3569, 2022 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-35246551

RESUMEN

The mechanism through which nonlinearity is generated in the response waveform of the electric current obtained by applying alternating current voltage to yeast suspension has not yet been elucidated. In this paper, we showed that the response waveform depends on the applied voltage and frequency. The results showed that distortion (nonlinearity) in the waveform increases as the applied voltage increases and/or the frequency decreases. We suggest a model for the generation of nonlinearity based on the influx of potassium ions into the cell via potassium ion channels and transporters in the membrane due to the applied voltage. Furthermore, we validated this model by simulating an electrical circuit.


Asunto(s)
Canales de Potasio , Saccharomyces cerevisiae , Electricidad , Potasio/metabolismo , Saccharomyces cerevisiae/metabolismo , Suspensiones
20.
Fungal Syst Evol ; 10: 217-229, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36741553

RESUMEN

The genus Spirodecospora has been placed in Xylariaceae based on morphological similarities. Spirodecospora spp., found on bamboo in Japan, were taxonomically and phylogenetically studied using molecular data for first time. Molecular phylogenetic analyses were based on the DNA sequence data of three regions: the nuclear ribosomal internal transcribed spacer (ITS) region, the large subunit (LSU) of rDNA, and the second largest RNA polymerase II subunit (rpb2) gene. Results showed that Spirodecospora formed an independent lineage from other known families in Xylariales. The new family Spirodecosporaceae is introduced in this study to accommodate this lineage based on the phylogenetic evidence and morphological differences from the other known families. Spirodecospora is characterised by having deeply immersed ascomata with a cylindrical ostiolar neck, unitunicate, cylindrical asci with I+, wedge-shaped apical ring, and broadly ellipsoidal to fusoid, aseptate, brown, verruculose ascospores with spirally or almost straight linear ornamentation. Based on morphological observations and molecular phylogenetic analyses, S. melnikii and two new species of Spirodecospora, S. paramelnikii and S. paulospiralis, are described and illustrated. A key to the four accepted species of Spirodecospora is provided. Citation: Sugita R, Hirayama K, Shirouzu T, Tanaka K (2022). Spirodecosporaceae fam. nov. (Xylariales, Sordariomycetes) and two new species of Spirodecospora. Fungal Systematics and Evolution 10: 217-229. doi: 10.3114/fuse.2022.10.09.

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