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1.
Rev Sci Instrum ; 95(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38477654

RESUMO

For the first time, details of the spatial and temporal acceptable evolution of the merging process of co-rotating electron vortices in a potential well are successfully captured using a "single-shot method" with a high temporal resolution of 10 µs. Four-electron filaments are trapped inside the Beam eXperiment-Upgrade linear trap [H. Himura, Nucl. Instrum. Methods Phys. Res. A 811, 100 (2016)] with a uniform axial magnetic field and co-axial multi-ring electrodes. Images of non-emitting electron filaments are captured using a high-speed camera with up to 1 000 000 fps, a microchannel plate, a fast-decay phosphor screen of which fluorescence duration is 0.15 µs, and a super fine metallic mesh with an open area ratio of 89%. Images captured every 10 µs clearly show the growth of multiple short-wave instabilities in the wing trailing electron vortices. The experimental methods and measurement techniques presented in this paper can contribute to revealing exactly how small vortices evolve into a large structure or turbulence in a potential well through complex processes.

2.
Actas Urol Esp (Engl Ed) ; 47(5): 317-326, 2023 06.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37272323

RESUMO

INTRODUCTION AND OBJECTIVES: Although the complications of intravesical BCG treatment are well described, asymptomatic genitourinary granulomas after BCG therapy have rarely been reported and management strategy for these conditions remains controversial. The objective of this study is to evaluate the incidence rate of asymptomatic genitourinary granuloma formation mimicking bladder cancer recurrence after intravesical bacillus Calmette-Guérin (BCG) therapy and to identify the diagnostic and treatment strategies according to patient conditions. PATIENTS AND METHODS: A retrospective review was conducted on 162 patients who underwent intravesical BCG therapy. For patients who developed granulomas, we evaluated the time interval between BCG instillation and the development of granuloma, the presence of acid-fast bacteria on pathology specimens, culture/polymerase chain reaction results, management strategies for the lesions, and clinical outcomes. RESULTS: Asymptomatic genitourinary masses developed in 14 patients, of whom 5 underwent histological examinations and all were confirmed to have granulomatous inflammation. The affected organs included the kidney, bladder, prostate, and penis. While four of the five patients did not receive treatment for their granulomas, one patient was administered antituberculous medication to prevent worsening of the lesion during the perioperative period of the scheduled cystoprostatectomy. None of the patients experienced worsening or recurrence of granulomatous lesions. Patients who developed asymptomatic masses (n = 14) were significantly younger than those who did not (p = 0.0076) and multivariate analysis also showed that younger age was independently associated with the development of clinically suspicious lesions (p = 0.032); however, none of the parameters were associated with histologically confirmed granuloma formation. CONCLUSIONS: Genitourinary granulomas mimicking recurrence of carcinoma may develop in nearly 10% of patients after intravesical BCG therapy. Most patients can be managed without potentially toxic antituberculosis therapy.


Assuntos
Vacina BCG , Neoplasias da Bexiga Urinária , Masculino , Humanos , Vacina BCG/efeitos adversos , Incidência , Recidiva Local de Neoplasia/epidemiologia , Neoplasias da Bexiga Urinária/patologia , Granuloma/etiologia , Granuloma/microbiologia
3.
Actas urol. esp ; 47(5): 317-326, jun. 2023. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-221364

RESUMO

Introducción y objetivos Aunque las complicaciones de la terapia intravesical con el bacilo de Calmette-Guérin (BCG) están bien descritas, pocas veces se ha comunicado la formación posterior de granulomas genitourinarios asintomáticos, y su estrategia de tratamiento sigue siendo controvertida. El objetivo de este estudio es evaluar la tasa de incidencia de la formación de granulomas genitourinarios asintomáticos que imitan la recurrencia del cáncer de vejiga tras el tratamiento intravesical con el BCG, así como identificar las estrategias de diagnóstico y tratamiento según las características de los pacientes. Pacientes y métodos Se realizó una revisión retrospectiva de 162 pacientes sometidos a terapia intravesical con BCG. En los pacientes que desarrollaron granulomas, se evaluó el intervalo de tiempo entre la instilación de BCG y el desarrollo del granuloma, la presencia de bacterias acidorresistentes en las muestras de patología, los resultados del cultivo/reacción en cadena de la polimerasa, las estrategias de tratamiento de las lesiones y los resultados clínicos. Resultados Se desarrollaron masas genitourinarias asintomáticas en 14 pacientes, de los cuales 5 se sometieron a evaluaciones histológicas confirmando en todos los casos una inflamación granulomatosa. Los órganos afectados fueron el riñón, la vejiga, la próstata y el pene. Aunque 5 de los 5 pacientes no recibieron tratamiento para los granulomas, a uno de ellos se le administró medicación antituberculosa para evitar el empeoramiento de la lesión durante el periodo perioperatorio de la cistoprostatectomía programada. Ninguno de los pacientes experimentó empeoramiento o recurrencia de las lesiones granulomatosas. Los pacientes que desarrollaron masas asintomáticas (n=14) eran significativamente más jóvenes que ...(AU)


Introduction and objectives Although the complications of intravesical BCG treatment are well described, asymptomatic genitourinary granulomas after BCG therapy have rarely been reported and management strategy for these conditions remains controversial. The objective of this study is to evaluate the incidence rate of asymptomatic genitourinary granuloma formation mimicking bladder cancer recurrence after intravesical bacillus Calmette-Guérin (BCG) therapy and to identify the diagnostic and treatment strategies according to patient conditions.Patients and methods A retrospective review was conducted on 162 patients who underwent intravesical BCG therapy. For patients who developed granulomas, we evaluated the time interval between BCG instillation and the development of granuloma, the presence of acid-fast bacteria on pathology specimens, culture/polymerase chain reaction results, management strategies for the lesions, and clinical outcomes. Results Asymptomatic genitourinary masses developed in 14 patients, of whom 5 underwent histological examinations and all were confirmed to have granulomatous inflammation. The affected organs included the kidney, bladder, prostate, and penis. While four of the five patients did not receive treatment for their granulomas, one patient was administered antituberculous medication to prevent worsening of the lesion during the perioperative period of the scheduled cystoprostatectomy. None of the patients experienced worsening or recurrence of granulomatous lesions. Patients who developed asymptomatic masses (n=14) were significantly younger than those who did not (P=.0076) and multivariate analysis also showed that younger age was independently associated with the development of clinically suspicious lesions (P=.032); however, none of the parameters were associated with histologically confirmed granuloma formation...(AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Neoplasias Urogenitais/terapia , Adjuvantes Imunológicos/administração & dosagem , Granuloma/terapia , Vacina BCG/administração & dosagem , Administração Intravesical , Estudos Retrospectivos , Incidência
5.
Nat Commun ; 13(1): 364, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35042881

RESUMO

The near-Earth asteroid (162173) Ryugu, the target of Hayabusa2 space mission, was observed via both orbiter and the lander instruments. The infrared radiometer on the MASCOT lander (MARA) is the only instrument providing spectrally resolved mid-infrared (MIR) data, which is crucial for establishing a link between the asteroid material and meteorites found on Earth. Earlier studies revealed that the single boulder investigated by the lander belongs to the most common type found on Ryugu. Here we show the spectral variation of Ryugu's emissivity using the complete set of in-situ MIR data and compare it to those of various carbonaceous chondritic meteorites, revealing similarities to the most aqueously altered ones, as well as to asteroid (101955) Bennu. The results show that Ryugu experienced strong aqueous alteration prior to any dehydration.

6.
Appl Opt ; 60(10): B8-B13, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33798131

RESUMO

Digital holography (DH) with two wavelengths (TW) that are close to each other was applied to height measurement of solder bumps having spherical specular surfaces with diameters of ∼20µm and heights of ∼20µm. We employed the parallel phase shifting method for instantaneous image capturing, and we improved the spatial resolution of our TW-DH system having two beams with different wavelengths that traveled in opposite directions in the interferometer. It gave 74-times higher repetition and 2.4-times higher spatial resolution than those in our previous DH system based on the Fourier transform method.

7.
Rev Sci Instrum ; 92(3): 035003, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33820008

RESUMO

Trapped magnetic flux in bulk superconductors reduces the quality factor Q in superconducting radio-frequency (SRF) cavities. However, the mechanisms underlying flux trapping and radio-frequency loss are not well understood. Detailed observation of the magnetic distributions is important for understanding such phenomena. Magnetic field mapping is useful for observing the magnetic field distribution around SRF cavities. Measuring the change in the magnetic field around the cavity elucidates the flux trapping behavior. Anisotropic magnetoresistive (AMR) sensors are inexpensive and small devices that can detect magnetic flux density. The magnetic sensitivities of AMR sensors need to be evaluated at liquid helium temperature for the magnetic field mapping of SRF cavities. In this study, a test stand was constructed to calibrate the magnetic sensitivities of AMR sensors in liquid helium, and 110 AMR sensors were tested using this stand. The magnetic sensitivities were evaluated systematically. A solenoid coil was used to control the uniform external magnetic field and to measure the magnetic sensitivity at low temperatures. All AMR sensors exhibited suitable sensitivities to the magnetic field around the SRF cavity. The variation in these sensitivities in all AMR sensors was ∼1%. The AMR sensors were found to have sufficient sensitivity for mapping the magnetic field around the exterior surface of the SRF cavity.

8.
Sci Rep ; 11(1): 2084, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33483553

RESUMO

The fusion power density produced in a tokamak is proportional to its magnetic field strength to the fourth power. Second-generation high temperature superconductor (2G HTS) wires demonstrate remarkable engineering current density (averaged over the full wire), JE, at very high magnetic fields, driving progress in fusion and other applications. The key challenge for HTS wires has been to offer an acceptable combination of high and consistent superconducting performance in high magnetic fields, high volume supply, and low price. Here we report a very high and reproducible JE in practical HTS wires based on a simple YBa2Cu3O7 (YBCO) superconductor formulation with Y2O3 nanoparticles, which have been delivered in just nine months to a commercial fusion customer in the largest-volume order the HTS industry has seen to date. We demonstrate a novel YBCO superconductor formulation without the c-axis correlated nano-columnar defects that are widely believed to be prerequisite for high in-field performance. The simplicity of this new formulation allows robust and scalable manufacturing, providing, for the first time, large volumes of consistently high performance wire, and the economies of scale necessary to lower HTS wire prices to a level acceptable for fusion and ultimately for the widespread commercial adoption of HTS.

10.
Rev Sci Instrum ; 91(1): 016103, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32012552

RESUMO

We established a production method of a millimeter-wave absorber by using a 3D-printed mold. The mold has a periodic pyramid shape, and an absorptive material is filled into the mold. This shape reduces the surface reflection. The 3D-printed mold is made from a transparent material in the millimeter-wave range. Therefore, unmolding is not necessary. A significant benefit of this production method is easy prototyping with various shapes and various absorptive materials. We produced a test model and used a two-component epoxy encapsulant as the absorptive material. The test model achieved a low reflectance: ∼1% at 100 GHz. The absorber is sometimes maintained at a low temperature condition for cases in which superconducting detectors are used. Therefore, cryogenic performance is required in terms of a mechanical strength for the thermal cycles, an adhesive strength, and a sufficient thermal conductivity. We confirmed the test-model strength by immersing the model into a liquid-nitrogen bath.

11.
Science ; 365(6455): 817-820, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31439797

RESUMO

The near-Earth asteroid (162173) Ryugu is a 900-m-diameter dark object expected to contain primordial material from the solar nebula. The Mobile Asteroid Surface Scout (MASCOT) landed on Ryugu's surface on 3 October 2018. We present images from the MASCOT camera (MASCam) taken during the descent and while on the surface. The surface is covered by decimeter- to meter-sized rocks, with no deposits of fine-grained material. Rocks appear either bright, with smooth faces and sharp edges, or dark, with a cauliflower-like, crumbly surface. Close-up images of a rock of the latter type reveal a dark matrix with small, bright, spectrally different inclusions, implying that it did not experience extensive aqueous alteration. The inclusions appear similar to those in carbonaceous chondrite meteorites.

12.
Science ; 364(6437): 272-275, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30890589

RESUMO

The near-Earth asteroid 162173 Ryugu, the target of the Hayabusa2 sample-return mission, is thought to be a primitive carbonaceous object. We report reflectance spectra of Ryugu's surface acquired with the Near-Infrared Spectrometer (NIRS3) on Hayabusa2, to provide direct measurements of the surface composition and geological context for the returned samples. A weak, narrow absorption feature centered at 2.72 micrometers was detected across the entire observed surface, indicating that hydroxyl (OH)-bearing minerals are ubiquitous there. The intensity of the OH feature and low albedo are similar to thermally and/or shock-metamorphosed carbonaceous chondrite meteorites. There are few variations in the OH-band position, which is consistent with Ryugu being a compositionally homogeneous rubble-pile object generated from impact fragments of an undifferentiated aqueously altered parent body.

13.
Science ; 364(6437): 268-272, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30890588

RESUMO

The Hayabusa2 spacecraft arrived at the near-Earth carbonaceous asteroid 162173 Ryugu in 2018. We present Hayabusa2 observations of Ryugu's shape, mass, and geomorphology. Ryugu has an oblate "spinning top" shape, with a prominent circular equatorial ridge. Its bulk density, 1.19 ± 0.02 grams per cubic centimeter, indicates a high-porosity (>50%) interior. Large surface boulders suggest a rubble-pile structure. Surface slope analysis shows Ryugu's shape may have been produced from having once spun at twice the current rate. Coupled with the observed global material homogeneity, this suggests that Ryugu was reshaped by centrifugally induced deformation during a period of rapid rotation. From these remote-sensing investigations, we identified a suitable sample collection site on the equatorial ridge.

14.
Science ; 364(6437): 252, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30890587

RESUMO

The near-Earth carbonaceous asteroid 162173 Ryugu is thought to have been produced from a parent body that contained water ice and organic molecules. The Hayabusa2 spacecraft has obtained global multicolor images of Ryugu. Geomorphological features present include a circum-equatorial ridge, east-west dichotomy, high boulder abundances across the entire surface, and impact craters. Age estimates from the craters indicate a resurfacing age of [Formula: see text] years for the top 1-meter layer. Ryugu is among the darkest known bodies in the Solar System. The high abundance and spectral properties of boulders are consistent with moderately dehydrated materials, analogous to thermally metamorphosed meteorites found on Earth. The general uniformity in color across Ryugu's surface supports partial dehydration due to internal heating of the asteroid's parent body.

16.
AJNR Am J Neuroradiol ; 39(2): 265-272, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29301781

RESUMO

BACKGROUND AND PURPOSE: Amide proton transfer imaging has been successfully applied to brain tumors, however, the relationships between amide proton transfer and other quantitative imaging values have yet to be investigated. The aim was to examine the additive value of amide proton transfer imaging alongside [18F] FDG-PET and DWI for preoperative grading of gliomas. MATERIALS AND METHODS: Forty-nine patients with newly diagnosed gliomas were included in this retrospective study. All patients had undergone MR imaging, including DWI and amide proton transfer imaging on 3T scanners, and [18F] FDG-PET. Logistic regression analyses were conducted to examine the relationship between each imaging parameter and the presence of high-grade (grade III and/or IV) glioma. These parameters included the tumor-to-normal ratio of FDG uptake, minimum ADC, mean amide proton transfer value, and their combinations. In each model, the overall discriminative power for the detection of high-grade glioma was assessed with receiver operating characteristic curve analysis. Additive information from minimum ADC and mean amide proton transfer was also evaluated by continuous net reclassification improvement. P < .05 was considered significant. RESULTS: Tumor-to-normal ratio, minimum ADC, and mean amide proton transfer demonstrated comparable diagnostic accuracy in differentiating high-grade from low-grade gliomas. When mean amide proton transfer was combined with the tumor-to-normal ratio, the continuous net reclassification improvement was 0.64 (95% CI, 0.036-1.24; P = .04) for diagnosing high-grade glioma and 0.95 (95% CI, 0.39-1.52; P = .001) for diagnosing glioblastoma. When minimum ADC was combined with the tumor-to-normal ratio, the continuous net reclassification improvement was 0.43 (95% CI, -0.17-1.04; P = .16) for diagnosing high-grade glioma, and 1.36 (95% CI, 0.79-1.92; P < .001) for diagnosing glioblastoma. CONCLUSIONS: Addition of amide proton transfer imaging to FDG-PET/CT may improve the ability to differentiate high-grade from low-grade gliomas.


Assuntos
Glioma/diagnóstico por imagem , Gradação de Tumores/métodos , Neuroimagem/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adulto , Idoso , Neoplasias Encefálicas/patologia , Feminino , Fluordesoxiglucose F18 , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
18.
Transl Psychiatry ; 7(8): e1214, 2017 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-28892071

RESUMO

Reticulon 4 receptor (RTN4R) plays an essential role in regulating axonal regeneration and plasticity in the central nervous system through the activation of rho kinase, and is located within chromosome 22q11.2, a region that is known to be a hotspot for schizophrenia (SCZ) and autism spectrum disorder (ASD). Recently, rare variants such as copy-number variants and single-nucleotide variants have been a focus of research because of their large effect size associated with increased susceptibility to SCZ and ASD and the possibility of elucidating the pathophysiology of mental disorder through functional analysis of the discovered rare variants. To discover rare variants with large effect size and to evaluate their role in the etiopathophysiology of SCZ and ASD, we sequenced the RTN4R coding exons with a sample comprising 370 SCZ and 192 ASD patients, and association analysis using a large number of unrelated individuals (1716 SCZ, 382 ASD and 4009 controls). Through this mutation screening, we discovered four rare (minor allele frequency <1%) missense mutations (R68H, D259N, R292H and V363M) of RTN4R. Among these discovered rare mutations, R292H was found to be significantly associated with SCZ (P=0.048). Furthermore, in vitro functional assays showed that the R292H mutation affected the formation of growth cones. This study strengthens the evidence for association between rare variants within RTN4R and SCZ, and may shed light on the molecular mechanisms underlying the neurodevelopmental disorder.


Assuntos
Transtorno do Espectro Autista/genética , Receptor Nogo 1/genética , Esquizofrenia/genética , Adolescente , Adulto , Transtorno do Espectro Autista/fisiopatologia , Criança , Éxons , Feminino , Frequência do Gene , Cones de Crescimento/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Mutação de Sentido Incorreto , Polimorfismo de Nucleotídeo Único/genética , Esquizofrenia/fisiopatologia , Adulto Jovem , Quinases Associadas a rho/metabolismo
19.
Transl Psychiatry ; 7(8): e1184, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28763059

RESUMO

CX3CR1, a G protein-coupled receptor solely expressed by microglia in the brain, has been repeatedly reported to be associated with neurodevelopmental disorders including schizophrenia (SCZ) and autism spectrum disorders (ASD) in transcriptomic and animal studies but not in genetic studies. To address the impacts of variants in CX3CR1 on neurodevelopmental disorders, we conducted coding exon-targeted resequencing of CX3CR1 in 370 Japanese SCZ and 192 ASD patients using next-generation sequencing technology, followed by a genetic association study in a sample comprising 7054 unrelated individuals (2653 SCZ, 574 ASD and 3827 controls). We then performed in silico three-dimensional (3D) structural modeling and in vivo disruption of Akt phosphorylation to determine the impact of the detected variant on CX3CR1-dependent signal transduction. We detected a statistically significant association between the variant Ala55Thr in CX3CR1 with SCZ and ASD phenotypes (odds ratio=8.3, P=0.020). A 3D structural model indicated that Ala55Thr could destabilize the conformation of the CX3CR1 helix 8 and affect its interaction with a heterotrimeric G protein. In vitro functional analysis showed that the CX3CR1-Ala55Thr mutation inhibited cell signaling induced by fractalkine, the ligand for CX3CR1. The combined data suggested that the variant Ala55Thr in CX3CR1 might result in the disruption of CX3CR1 signaling. Our results strengthen the association between microglia-specific genes and neurodevelopmental disorders.


Assuntos
Transtorno do Espectro Autista/genética , Receptor 1 de Quimiocina CX3C/genética , Esquizofrenia/genética , Adolescente , Adulto , Idoso , Criança , Simulação por Computador , Éxons , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo de Nucleotídeo Único , Adulto Jovem
20.
J Hand Surg Asian Pac Vol ; 22(2): 208-213, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28506161

RESUMO

BACKGROUND: The fatigue strength of three peripheral suture techniques for flexor tendon repair was compared by cyclic loading of the repairs in the porcine flexor digitorum tendon. METHODS: Thirty-six tendons were sutured using only peripheral sutures with 6-0 Nylon. An initial cyclic load of 10 N for 500 cycles was applied and increased by 10 N for an additional 500 cycles at each new load until rupture. RESULTS: The fatigue strength of the symmetric running peripheral suture was 85.0% and 144.8% greater than that of the two kinds of the asymmetric running peripheral sutures. CONCLUSIONS: Symmetric running sutures can enhance the suture strength and appears to be a useful technique for increasing the strength of the peripheral suture.


Assuntos
Técnicas de Sutura , Suturas , Tendões/cirurgia , Animais , Fenômenos Biomecânicos , Caprolactama/análogos & derivados , Polímeros , Suínos , Resistência à Tração , Técnicas de Cultura de Tecidos
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