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1.
Nano Lett ; 24(8): 2567-2573, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38367281

RESUMO

The boundary between CaRuO3 and CaMnO3 is an ideal test bed for emergent magnetic ground states stabilized through interfacial electron interactions. In this system, nominally antiferromagnetic and paramagnetic materials combine to yield interfacial ferromagnetism in CaMnO3 due to electron leakage across the interface. In this work, we show that the crystal symmetry at the surface is a critical factor determining the nature of the interfacial interactions. Specifically, by growing CaRuO3/CaMnO3 heterostructures along the (111) instead of the (001) crystallographic axis, we achieve a 3-fold enhancement of the magnetization and involve the CaRuO3 layers in the ferromagnetism, which now spans both constituent materials. The stabilization of a net magnetic moment in CaRuO3 through strain effects has been long-sought but never consistently achieved, and our observations demonstrate the importance of interface engineering in the development of new functional heterostructures.

3.
RSC Adv ; 13(43): 30491-30498, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37860175

RESUMO

Colloidal nanoparticles can be coated with a conformal shell to form multifunctional nanoparticles. For instance, plasmonic, magnetic, and catalytic properties, chemical stability and biocompatibility can be mixed and matched. Here, a facile synthesis for depositing metal boride amorphous coatings on colloidal metallic nanocrystals is introduced. The synthesis is independent of core size, shape, and composition. We have found that the shell synthesis is limited to nanoparticles capped with short molecular weight and low binding energy ligands, and does not work with polyvinylpyrrolidone (PVP)-coated Ag nanoparticles or thiol-coated Au nanoparticles. Shell thickness can be as thin as 3 nm with no apparent pinholes. High pressure studies show that the coatings are highly resistant to crystallization and are strongly bonded to the crystalline core. By choosing either CoB or NiB for the coating, the composite nanoparticles can be either ferromagnetic or paramagnetic at room temperature, respectively.

4.
Nat Commun ; 14(1): 4918, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37582804

RESUMO

Ultra-thin films of low damping ferromagnetic insulators with perpendicular magnetic anisotropy have been identified as critical to advancing spin-based electronics by significantly reducing the threshold for current-induced magnetization switching while enabling new types of hybrid structures or devices. Here, we have developed a new class of ultra-thin spinel structure Li0.5Al1.0Fe1.5O4 (LAFO) films on MgGa2O4 (MGO) substrates with: 1) perpendicular magnetic anisotropy; 2) low magnetic damping and 3) the absence of degraded or magnetic dead layers. These films have been integrated with epitaxial Pt spin source layers to demonstrate record low magnetization switching currents and high spin-orbit torque efficiencies. These LAFO films on MGO thus combine all of the desirable properties of ferromagnetic insulators with perpendicular magnetic anisotropy, opening new possibilities for spin based electronics.

5.
Nat Commun ; 14(1): 2393, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37100786

RESUMO

We present room-temperature measurements of magnon spin diffusion in epitaxial ferrimagnetic insulator MgAl0.5Fe1.5O4 (MAFO) thin films near zero applied magnetic field where the sample forms a multi-domain state. Due to a weak uniaxial magnetic anisotropy, the domains are separated primarily by 180° domain walls. We find, surprisingly, that the presence of the domain walls has very little effect on the spin diffusion - nonlocal spin transport signals in the multi-domain state retain at least 95% of the maximum signal strength measured for the spatially-uniform magnetic state, over distances at least five times the typical domain size. This result is in conflict with simple models of interactions between magnons and static domain walls, which predict that the spin polarization carried by the magnons reverses upon passage through a 180° domain wall.

6.
Nat Commun ; 14(1): 1406, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36918562

RESUMO

Spin-Hall nano-oscillators (SHNOs) are promising spintronic devices to realize current controlled GHz frequency signals in nanoscale devices for neuromorphic computing and creating Ising systems. However, traditional SHNOs devices based on transition metals have high auto-oscillation threshold currents as well as low quality factors and output powers. Here we demonstrate a new type of hybrid SHNO based on a permalloy (Py) ferromagnetic-metal nanowire and low-damping ferrimagnetic insulator, in the form of epitaxial lithium aluminum ferrite (LAFO) thin films. The superior characteristics of such SHNOs are associated with the excitation of larger spin-precession angles and volumes. We further find that the presence of the ferrimagnetic insulator enhances the auto-oscillation amplitude of spin-wave edge modes, consistent with our micromagnetic modeling. This hybrid SHNO expands spintronic applications, including providing new means of coupling multiple SHNOs for neuromorphic computing and advancing magnonics.

7.
Front Pediatr ; 10: 961935, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36545671

RESUMO

Purpose: Previous research has revealed vocational and academic difficulties in childhood cancer survivors, and explored impact of survivors' medical history and physical function on vocational and academic status. However, we often encounter survivors with similar diagnoses and late effects but different academic or employment statuses. This raises the question of what affects academic attainment and employment other than treatment or late effects. This study aimed to explore factors associated with childhood cancer survivors' employment status and academic achievement. Methods: Comprehensive health check-up and questionnaire survey were conducted for 69 survivors who were over the age of 18 and participated in St. Luke's Lifetime cohort study. We obtained survivors' biological function using comprehensive health check-up, neurocognitive states, quality of life, transition readiness, and family function. We conducted univariate analysis (Mann-Whitney U tests or chi-square tests) to compare the differences between the regular workers/students and non-regular workers/unemployed groups. The variables with p-values <0.1 were used as independent variables multivariate logistic regression to explore predictors of employment status and academic attainment. Results: Result of the univariate analysis, intelligence quotient, SF-8 PCS, transition readiness, family function were used for multivariate logistic regression as independent variables. The stepwise likelihood method was conducted; intelligence quotient (odds ratio [OR] = 1.100; 95% confidence interval [CI] 1.015-1.193; p = 0.021), transition readiness (OR = 0.612; 95% CI 0.396-0.974; p = 0.038), and family function (OR = 2.337; 95% CI 1.175-4.645; p = 0.015) were found to be associated with survivors' regular workers/students in the final regression model. Conclusion: Long-term follow-up of pediatric cancer survivors requires the provision of total care, which supports physical, psychological, and social functions to improve health, readiness for transition to self-management, and family functioning.

8.
Front Pediatr ; 10: 947646, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275067

RESUMO

Background: Childhood cancer survivors (CCSs) have a lifelong increased risk of chronic health problems, most of which are associated with the curative therapies. Recent studies have suggested that prospective active screening using comprehensive assessments for CCSs is superior in identifying undiagnosed chronic health problems. Methods: To assess the significance of active screening using comprehensive medical examinations for detecting chronic health problems in multiple organ systems in CCSs, we retrospectively compared the frequency and severity of health problems between two different cohorts of CCSs in a single institution: 110 CCSs who visited the outpatient clinic for regular follow-ups between December 2010 and December 2015 (regular follow-up group) vs. 58 CCSs who underwent comprehensive medical examinations between February 2016 and September 2019 (active screening group). CCSs were defined as patients aged ≥ 18 years who had been diagnosed as having childhood cancer ≥ 10 years before and had survived without cancer for ≥ 5 years. Results: Patient characteristics were similar between the two groups except for primary diagnosis (more brain tumors and embryonal tumors in the active screening group) and treatment history (more alkylating agents used and surgical interventions performed in the active screening group). The prevalence and the median number of health problems were significantly higher in the active screening group than in the regular follow-up group: 93% vs. 67% and 1.0 [0.0-8.0] vs. 2.0 [0.0-7.0] respectively. In term of organ-specific health problems, pulmonary dysfunction, neurocognitive impairment, ocular abnormalities, and dental abnormalities were identified more in the active screening group, partly because these problems had not been assessed in the regular follow-up group. Nevertheless, the prevalence of grade 3-5 health problems was similar between the two groups, except for pulmonary dysfunction. Conclusion: Active screening using comprehensive medical examinations was effective for identifying health problems in CCSs. Although the prevalence of severe problems identified by both approaches was similar, comprehensive medical examinations could detect overlooked problems such as severe pulmonary dysfunction, dental maldevelopment, and borderline intellectual functioning, which might have an impact on quality of life in CCSs.

9.
Phys Rev Lett ; 128(12): 126802, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35394317

RESUMO

Magnetic insulator-topological insulator heterostructures have been studied in search of chiral edge states via proximity induced magnetism in the topological insulator, but these states have been elusive. We identified MgAl_{0.5}Fe_{1.5}O_{4}/Bi_{2}Se_{3} bilayers for a possible magnetic proximity effect. Electrical transport and polarized neutron reflectometry suggest a proximity effect, but structural data indicate a disordered interface as the origin of the magnetic response. Our results provide a strategy via correlation of microstructure with magnetic data to confirm a magnetic proximity effect.

10.
J Pediatr Hematol Oncol ; 44(3): e779-e781, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35001057

RESUMO

A 4-month-old boy with abdominal distension was diagnosed with adrenal neuroblastoma with numerous metastases to the liver and nodules in the skin and muscles. Marked hepatomegaly spontaneously regressed with decreasing tumor marker levels, and the final diagnosis was stage M based on radiologic findings confirming metastasis to the pancreas. The neuroblastoma did not have the MYCN amplification but had an 11q aberration. Chemotherapy was initiated at age 6 months with a successful response. Our case reflects the heterogenous clinical behavior of neuroblastoma and highlights the challenging issue of the difference between stage M and stage MS neuroblastoma in infants.


Assuntos
Neoplasias das Glândulas Suprarrenais , Neuroblastoma , Neoplasias das Glândulas Suprarrenais/diagnóstico , Neoplasias das Glândulas Suprarrenais/genética , Aberrações Cromossômicas , Hepatomegalia , Humanos , Lactente , Masculino , Neuroblastoma/diagnóstico , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética
11.
JCI Insight ; 7(2)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35076023

RESUMO

Platelet-neutrophil aggregates (PNAs) facilitate neutrophil activation and migration and could underpin the recruitment of neutrophils to the pancreas during type 1 diabetes (T1D) pathogenesis. PNAs, measured by flow cytometry, were significantly elevated in the circulation of autoantibody-positive (Aab+) children and new-onset T1D children, as well as in pre-T1D (at 4 weeks and 10-12 weeks) and T1D-onset NOD mice, compared with relevant controls, and PNAs were characterized by activated P-selectin+ platelets. PNAs were similarly increased in pre-T1D and T1D-onset NOD isolated islets/insulitis, and immunofluorescence staining revealed increased islet-associated neutrophil extracellular trap (NET) products (myeloperoxidase [MPO] and citrullinated histones [CitH3]) in NOD pancreata. In vitro, cell-free histones and NETs induced islet cell damage, which was prevented by the small polyanionic drug methyl cellobiose sulfate (mCBS) that binds to histones and neutralizes their pathological effects. Elevated circulating PNAs could, therefore, act as an innate immune and pathogenic biomarker of T1D autoimmunity. Platelet hyperreactivity within PNAs appears to represent a previously unrecognized hematological abnormality that precedes T1D onset. In summary, PNAs could contribute to the pathogenesis of T1D and potentially function as a pre-T1D diagnostic.


Assuntos
Plaquetas/imunologia , Agregação Celular/imunologia , Diabetes Mellitus Tipo 1 , Armadilhas Extracelulares , Neutrófilos/imunologia , Pâncreas , Animais , Autoanticorpos/sangue , Criança , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/imunologia , Diagnóstico Precoce , Armadilhas Extracelulares/diagnóstico por imagem , Armadilhas Extracelulares/imunologia , Feminino , Imunofluorescência/métodos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Ativação de Neutrófilo/imunologia , Selectina-P/metabolismo , Pâncreas/imunologia , Pâncreas/patologia
12.
Nano Lett ; 22(3): 1167-1173, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35077185

RESUMO

Magnon-mediated spin flow in magnetically ordered insulators enables long-distance spin-based information transport with low dissipation. In the materials studied to date, no anisotropy has been observed in the magnon propagation length as a function of propagation direction. Here, we report measurements of magnon spin transport in a spinel ferrite, magnesium aluminum ferrite MgAl0.5Fe1.5O4 (MAFO), which has a substantial in-plane 4-fold magnetic anisotropy. We observe spin diffusion lengths > 0.8 µm at room temperature in 6 nm films, with spin diffusion lengths 30% longer along the easy axes compared to the hard axes. The sign of this difference is opposite to the effects just of anisotropy in the magnetic energy for a uniform magnetic state. We suggest instead that accounting for anisotropy in exchange stiffness is necessary to explain these results. These findings provide an approach for controlling magnon transport via strain, which opens new opportunities for designing magnonic devices.

13.
Rinsho Ketsueki ; 62(10): 1482-1487, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-34732620

RESUMO

The occurrence of a primary mediastinal germ cell tumor and hematological neoplasia provides a poor prognosis that is known to be fatal at a median of 6 months after onset. We report the case of a 15-year-old male who was treated with chemotherapy and hematopoietic cell transplantation based on a report of a surviving case. At diagnosis, the patient had an unresectable mediastinal tumor with elevated alpha-fetoprotein and human chorionic gonadotropin levels and acute megakaryoblastic leukemia. We prioritized treatment with chemotherapy for the tumor owing to the oncological emergency. We then performed leukemia induction therapy and achieved complete remission. Although we used CDDP in combination with intensive therapy, the mediastinal tumor grew too large for it to be safely resected. We transplanted bone marrow from the patient's human leukocyte antigen-haploidentical sibling upon conditioning with busulfan-melphalan. After 44 days, the leukemia recurred in the patient's central nervous system. This was followed by various post-transplant complications, and the patient died of organ failure that was associated with infectious diseases. At necropsy, a poorly engrafted bone marrow was observed. The mediastinal tumor was primarily necrotic, although some immature teratoma components were observed. No leukemic precursor cells were detected. Residual mediastinal tumors may be associated with the recurrence of leukemias. We seek a treatment strategy that enables early tumor resection and high-dose chemotherapy. Further case studies are warranted along with the development of effective treatment methods.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Megacarioblástica Aguda , Neoplasias do Mediastino , Neoplasias Embrionárias de Células Germinativas , Teratoma , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos , Masculino , Neoplasias do Mediastino/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/terapia
14.
Respirol Case Rep ; 9(10): e0847, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34540234

RESUMO

Pulmonary hypertension (PH) is a life-threatening disorder, which originates from various aetiologies. Ventilation-perfusion (V/Q) scanning is commonly used to evaluate the differential diagnosis of PH. Meanwhile, previous studies have shown that single-photon emission computed tomography (SPECT)/CT imaging can provide a more detailed analysis for the assessment of pulmonary blood flow. However, there is insufficient evidence supporting the merits of V/Q SPECT/CT image data in detecting pulmonary vascular disease. Here, we report a case of pulmonary arterial hypertension with localized accumulation and peculiar distribution just below the pleura on V/Q SPECT/CT. Our finding is unique, and it suggests that V/Q SPECT/CT image data might be useful to detect blood flow not only in cases of pulmonary embolism, but also in the more commonly encountered PH.

15.
Gynecol Oncol Rep ; 35: 100684, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33364289

RESUMO

•We report the first case of a paraurethral mixed Müllerian cystadenoma.•The cystic lesion was lined by a mixture of three different types of epithelium.•All epithelial cells were positive for estrogen receptor and PAX8.

16.
Front Immunol ; 12: 784901, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35087518

RESUMO

IKAROS and CTLA4 deficiencies are inborn errors of immunity and show similar clinical phenotypes, including hypogammaglobulinemia and autoimmune diseases (ADs). However, the differences in clinical features and pathogenesis of these are not fully understood. Therefore, we performed systematic literature reviews for IKAROS and CTLA4 deficiencies. The reviews suggested that patients with IKAROS deficiency develop AD earlier than hypogammaglobulinemia. However, no study assessed the detailed changes in clinical manifestations over time; this was likely due to the cross-sectional nature of the studies. Therefore, we conducted a retrospective longitudinal study on IKAROS and CTLA4 deficiencies in our cohort to evaluate the clinical course over time. In patients with IKAROS deficiency, AD and hypogammaglobulinemia often develop in that order, and AD often resolves before the onset of hypogammaglobulinemia; these observations were not found in patients with CTLA4 deficiency. Understanding this difference in the clinical course helps in the clinical management of both. Furthermore, our results suggest B- and T-cell-mediated ADs in patients with IKAROS and CTLA4 deficiencies, respectively.


Assuntos
Antígeno CTLA-4/deficiência , Fator de Transcrição Ikaros/deficiência , Erros Inatos do Metabolismo , Doenças Autoimunes , Humanos , Estudos Longitudinais , Doenças da Imunodeficiência Primária , Estudos Retrospectivos
18.
Nat Commun ; 11(1): 902, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32060300

RESUMO

Electric fields can transform materials with respect to their structure and properties, enabling various applications ranging from batteries to spintronics. Recently electrolytic gating, which can generate large electric fields and voltage-driven ion transfer, has been identified as a powerful means to achieve electric-field-controlled phase transformations. The class of transition metal oxides provide many potential candidates that present a strong response under electrolytic gating. However, very few show a reversible structural transformation at room-temperature. Here, we report the realization of a digitally synthesized transition metal oxide that shows a reversible, electric-field-controlled transformation between distinct crystalline phases at room-temperature. In superlattices comprised of alternating one-unit-cell of SrIrO3 and La0.2Sr0.8MnO3, we find a reversible phase transformation with a 7% lattice change and dramatic modulation in chemical, electronic, magnetic and optical properties, mediated by the reversible transfer of oxygen and hydrogen ions. Strikingly, this phase transformation is absent in the constituent oxides, solid solutions and larger period superlattices. Our findings open up this class of materials for voltage-controlled functionality.

19.
Plant Foods Hum Nutr ; 74(4): 538-543, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31728799

RESUMO

Our previous study showed anti-influenza virus activity in adlay tea prepared from adlay seeds, naked barley seeds, soybean, and cassia seeds. In this study, we evaluated the anti-influenza virus activity of each component of this tea and analyzed their active ingredients. Each component was roasted and extracted in hot water; the extracts were tested for antiviral activity and their mechanisms of action were studied. All the tea components showed antiviral activity against the H1N1 and H3N2 influenza subtypes and against influenza B. The viral stages inhibited by the components were virus adsorption and replication in proliferative process, suggesting that the action mechanisms of the components might differ from those of oseltamivir acid. Of the tea components, soybean showed the strongest activity. Therefore, we analyzed its active ingredients by liquid chromatography quadruple time-of-flight mass spectrometry (LC/qTOF-MS) and daidzein and glycitein were detected as active ingredients. Here, anti-influenza virus action of glycitein was the first report.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Humanos , Vírus da Influenza A Subtipo H3N2 , Chá , Replicação Viral
20.
Bio Protoc ; 9(16): e3342, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-33654846

RESUMO

Here, we describe a sorbitol-based optical clearing method, called modified Sca/eS that can be used to image all hair cells (HCs) in the mouse cochlea. This modification of Sca/eS is defined by three steps: decalcification, de-lipidation, and refractive index matching, which can all be completed within 72 h. Furthermore, we established automated analysis programs that perform machine learning-based pattern recognition. These programs generate 1) a linearized image of HCs, 2) the coordinates of HCs, 3) a holocochleogram, and 4) clusters of HC loss. In summary, a novel approach that integrates modified Sca/eS and programs based on machine learning facilitates quantitative and comprehensive analysis of the physiological and pathological properties of all HCs.

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