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1.
Sci Rep ; 13(1): 10071, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37344550

RESUMO

We performed a preliminary study of neutron resonance absorption imaging to investigate the spatial distribution of constituent elements in borosilicate glasses containing simulated high-level radioactive waste, in which elemental inhomogeneities affect the physical and chemical stabilities of the glass. Dips generated by the resonance absorptions of Rh, Pd, Na, Gd, Cs, and Sm were observed in the neutron transmission spectra of the glass samples. The spatial distributions of these elements were obtained from the neutron transmission images at the resonance energies. The distributions of Rh and Pd visualized the sedimentation of these platinum group elements. In contrast, the lanthanides (Gd and Sm) and Cs were uniformly dispersed. These results show that neutron resonance absorption imaging is a promising tool for characterizing borosilicate glasses and investigating the vitrification mechanism of high-level radioactive waste.

2.
Sci Rep ; 11(1): 16539, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34400683

RESUMO

In many phenomena of biological systems, not a majority, but a minority of cells act on the entire multicellular system causing drastic changes in the system properties. To understand the mechanisms underlying such phenomena, it is essential to observe the spatiotemporal dynamics of a huge population of cells at sub-cellular resolution, which is difficult with conventional tools such as microscopy and flow cytometry. Here, we describe an imaging system named AMATERAS that enables optical imaging with an over-one-centimeter field-of-view and a-few-micrometer spatial resolution. This trans-scale-scope has a simple configuration, composed of a low-power lens for machine vision and a hundred-megapixel image sensor. We demonstrated its high cell-throughput, capable of simultaneously observing more than one million cells. We applied it to dynamic imaging of calcium ions in HeLa cells and cyclic-adenosine-monophosphate in Dictyostelium discoideum, and successfully detected less than 0.01% of rare cells and observed multicellular events induced by these cells.


Assuntos
Células/citologia , Microscopia de Fluorescência/métodos , Animais , Encéfalo/citologia , Cálcio/análise , AMP Cíclico/análise , Dictyostelium/química , Dictyostelium/ultraestrutura , Cães , Entose , Células Epiteliais/ultraestrutura , Desenho de Equipamento , Proteínas de Fluorescência Verde , Células HeLa/química , Células HeLa/ultraestrutura , Humanos , Interneurônios/ultraestrutura , Proteínas Luminescentes , Células Madin Darby de Rim Canino , Camundongos , Microscopia de Fluorescência/instrumentação , Neurônios/ultraestrutura , Semicondutores , Proteína Vermelha Fluorescente
3.
Dis Esophagus ; 32(3)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30085020

RESUMO

Neoadjuvant chemotherapy (NAC) is administered to many patients with esophageal squamous cell carcinoma (ESCC) prior to surgery, but it is also true that some of these patients demonstrated no response to the therapy following surgery. In addition, the prognosis of advanced case such as ESCC patients with lymph node metastasis has remained relatively low. Programmed death ligand-1 (PD-L1) in conjunction with tumor-infiltrating lymphocytes (TILs) has been studied as a potential mechanism of "immune escape" in several human malignancies. Therefore, in this study, we studied PD-L1 status in carcinoma cells and forkhead box protein 3 (FOXP3) and CD8 status among TILs in the residual tumors of primary and metastatic sites following NAC. We also studied the association of these factors with the clinicopathological findings in 44 patients with ESCC harboring lymph node metastasis. There was discordance in the pathological response to chemotherapy between the primary tumor and lymph node metastasis, and histologically identified resistance to NAC in lymph node metastases tended to be correlated with an adverse clinical outcome (P = 0.0765) than resistance in the primary tumor. Both univariate and multivariate analyses for disease-specific survival (DSS) revealed that the PD-L1 status of carcinoma cells in metastatic lymph nodes and a higher FOXP3/CD8 ratio in the primary tumor were both significantly correlated with an eventual adverse clinical outcome of the patients (P = 0.0178, P = 0.0463, respectively). These results all indicated that the PD-L1 status of carcinoma cells in metastatic lymph nodes and the FOXP3/CD8 ratio in primary tumors could predict eventual clinical outcomes in ESCC patients with NAC.


Assuntos
Antígeno B7-H1/metabolismo , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Linfócitos do Interstício Tumoral/metabolismo , Terapia Neoadjuvante/mortalidade , Antígenos CD8/metabolismo , Quimioterapia Adjuvante/mortalidade , Terapia Combinada , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/mortalidade , Carcinoma de Células Escamosas do Esôfago/patologia , Esofagectomia/mortalidade , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Linfonodos/metabolismo , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Resultado do Tratamento
4.
Genes Brain Behav ; 17(8): e12478, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29635888

RESUMO

Disrupted-in-schizophrenia 1 (Disc1) is a key molecular driver for the biology of mental diseases. In order to investigate its role in brain function, we previously generated mice lacking exons 2 and 3 of Disc1 on a C57BL/6J genetic background (Disc1Δ2-3/Δ2-3 mice), which have a deficiency of the full-length Disc1 protein. In the present study, we examined the role of Disc1 in cognitive function using a touchscreen-based visual discrimination (VD) task in which mice had to discriminate 1 of 2 stimuli simultaneously displayed on the screen and received a liquid reward. Disc1Δ2-3/Δ2-3 mice showed impaired performance in the VD task, and this was mainly attributed to the perseverative response being significantly stronger than that in wild-type (WT) mice. Furthermore, the numbers of marbles buried in the marble burying test and nestlets shredded in the nestlet shredding test by Disc1Δ2-3/Δ2-3 mice were significantly higher than those by WT mice, suggesting perseverative/compulsive behaviors by Disc1Δ2-3/Δ2-3 mice. A treatment with clozapine ameliorated behavioral deficits in the VD and marble burying tasks. c-Fos expression was significantly stronger in the dorsomedial striatum (DMS), but not the dorsolateral striatum (DLS) after the first VD session in Disc1Δ2-3/Δ2-3 mice than in WT mice. The treatment of mice that had previously expressed hM3Dq in the DMS with clozapine-N-oxide (CNO) impaired performance in the VD task. These results suggest that cognitive impairments accompanied by perseverative/compulsive behaviors in Disc1Δ2-3/Δ2-3 mice are associated with hyperactivity of the DMS.


Assuntos
Comportamento Compulsivo/fisiopatologia , Proteínas do Tecido Nervoso/metabolismo , Transtorno de Movimento Estereotipado/fisiopatologia , Animais , Comportamento Animal/fisiologia , Clozapina , Cognição , Disfunção Cognitiva/genética , Modelos Animais de Doenças , Éxons , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Estimulação Luminosa
5.
HLA ; 2018 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-29653015

RESUMO

We describe the identification of alternatively expressed HLA allele C*07:02:01:17N.

6.
J Food Sci Technol ; 55(2): 586-597, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29391623

RESUMO

The chemical parameters and the functionalities of six monofloral honeys of different botanical and geographical origins were investigated. Vitamins B1, B2, and C and the protein content of majority of honeys were distinguishable from general honey. Honeys not only were rich in a variety of functional components like flavonoids but also had strong anti-oxidant activities, scavenging activities against ROS, and anti-hypertensive and anti-allergic activities. Honeys were heated at 100 °C for 24 h and their browning intensity during heating process was observed to vary with botanical origin. The functional properties of caramelization and maillard reaction (MR) products derived from honeys during heating were evaluated. The browning of honeys progressed regardless of honey species. Anti-oxidant activities and scavenging activities against superoxide and DPPH radicals of products drastically increased, but ACE and hyaluronidase activities gradually decreased with passage of heating time. It concluded that the products, mainly melanoidins, produced simultaneously to browning process in caramelization and MR contributed to the expression of its useful function.

7.
Vox Sang ; 113(3): 297-299, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29359332

RESUMO

The risk of transfusion-transmitted infection (TTI) for severe fever with thrombocytopenia syndrome virus (SFTSV) is a concern because person-to-person transmission resulting from contact with SFTSV-contaminated blood has been reported. To obtain information regarding the risk of TTI-SFTSV, antibody testing was performed for blood samples donated in an severe fever with thrombocytopenia syndrome-endemic area in Japan. No antibody-positive samples were detected among 3990 samples. This finding suggested that there were few cases of SFTSV infection among donors and that the risk of TTI-SFTSV was also estimated low in Japan.


Assuntos
Infecções por Bunyaviridae/epidemiologia , Phlebovirus/imunologia , Reação Transfusional/epidemiologia , Adulto , Anticorpos Antivirais/sangue , Doadores de Sangue , Infecções por Bunyaviridae/sangue , Feminino , Humanos , Japão , Masculino , Phlebovirus/patogenicidade , Reação Transfusional/sangue , Reação Transfusional/virologia
8.
HLA ; 89(5): 285-292, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28256086

RESUMO

BACKGROUND AND OBJECTIVES: Human leukocyte antigen (HLA) antibodies, which are involved in the development of transfusion-related side effects such as transfusion-related lung injury, are sometimes found in males without a history of alloimmunization (eg, transplantation and transfusion). Whether HLA antibodies in male donors can interact with their target HLA specificities expressed on cells have not been completely investigated. MATERIALS AND METHODS: The HLA antibodies detected in 7 male donors were characterized. Flow cytometry and immunocomplex capture fluorescence analysis were performed to evaluate the ability of these antibodies to bind with target HLA specificities expressed on cells. The association of these antibodies with complement was examined using anti-C1q antibody. Sustainability of HLA antibodies over time was compared in 26 male vs 57 female donors. RESULTS: The antibodies from all 7 donors recognized intact HLA molecules coated onto microbeads. The antibodies in 2 of 7 donors also recognized their target HLA specificities expressed on cells. Furthermore, the antibodies in one of these 2 donors showed HLA specificities that involved complement binding. Twenty-one of 26 initially positive male donors had turned negative for HLA antibody at least 1 year after their initial positive screening, whereas HLA antibody positivity was maintained for a long time in most female donors. CONCLUSION: Males without apparent alloimmunization could have HLA antibodies that recognize their target HLA specificities on cells and that could potentially modify molecular events in affected cells.


Assuntos
Complexo Antígeno-Anticorpo/sangue , Doadores de Sangue , Proteínas do Sistema Complemento/metabolismo , Antígenos HLA/sangue , Isoanticorpos/sangue , Adulto , Especificidade de Anticorpos , Feminino , Citometria de Fluxo , Humanos , Masculino , Ligação Proteica , Fatores Sexuais , Lesão Pulmonar Aguda Relacionada à Transfusão/prevenção & controle
9.
Int Nurs Rev ; 63(2): 292-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26868263

RESUMO

BACKGROUND: The recent Fukushima Nuclear Power Plant accident was one of more than 200 serious nuclear/radiation incidents (accidents and disasters) that occurred worldwide since 1945. The current Fukushima disaster is in the recovery phase with the decreasing levels of radiation in the environment. However, fears and stigma related to the perceived risk of radiation exposure persist among the general population. INTRODUCTION: To improve on students' preparedness for social and public health challenges after a radiation incidence, radiation education was provided for undergraduate public health nursing students. AIM: This case study reports the development and implementation of the first class of radiation education in public health nursing, as well as students' reflections on their class experience. METHODS: We included a 90-min radiation class in an undergraduate public health nursing course in Tokyo, Japan. Lectures/discussion on technical and environmental aspects provided the minimally essential content for basic radiation knowledge. After class, all the 65 students were invited to freely write their reflections on the class. With their consent, 61 students' anonymous written accounts were qualitatively analysed. RESULTS: Five themes emerged: awareness of ignorance about radiation, problems produced by the mass media, becoming knowledgeable about radiation, public health nurses' role, and trustful and enjoyable lecture. DISCUSSION: The class inspired students to consider social, psychological and relational aspects of knowing and not knowing about radiation and their future professional role. CONCLUSION AND IMPLICATIONS FOR NURSING: Once radiation is taught at school, nursing students will emerge as professionals with the belief that radiation is within their professional purview. Education is key to disaster prevention, preparation, response and recovery. Given the ubiquitous nature of health challenges after a radiation incident, radiation education is indispensable for nursing students worldwide.


Assuntos
Educação em Enfermagem , Acidente Nuclear de Fukushima , Enfermagem em Saúde Pública , Desastres , Humanos , Japão , Estudantes de Enfermagem
10.
Clin Genet ; 89(5): 614-9, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26526156

RESUMO

Recent studies have suggested that disomic oocyte-mediated uniparental disomy 15 (UPD(15)mat) is increased in patients with Prader-Willi syndrome (PWS) born after medically assisted reproduction (MAR). However, it remains unknown whether the increase is primarily due to MAR procedure itself or advanced maternal childbearing ages as a predisposing factor for the disomic oocyte production. To examine this matter, we studied 122 naturally conceived PWS patients (PWS-NC group) and 13 MAR-conceived patients (PWS-MAR group). The relative frequency of disomic oocyte-mediated UPD(15)mat was significantly higher in PWS-MAR group than in PWS-NC group (7/13 vs 20/122, p = 0.0045), and the maternal childbearing ages were significantly higher in PWS-MAR group than in PWS-NC group [median (range), 38 (26-45) vs 30 (19-42), p = 0.0015]. However, the logistic regression analysis revealed no significant association between the occurrence of disomic oocyte-mediated UPD(15)mat and MAR, after adjusting for childbearing age (p = 0.25). Consistent with this, while the frequency of assisted reproductive technology (ART)-conceived livebirths was higher in the PWS patients than in the Japanese general population (6.4% vs 1.1%, p = 0.00018), the distribution of childbearing ages was significantly skewed to the increased ages in the PWS patients (p < 2.2 × 10(-16) ). These results argue against a positive association of MAR procedure itself with the development of UPD(15)mat.


Assuntos
Cromossomos Humanos Par 15/genética , Síndrome de Prader-Willi/genética , Técnicas de Reprodução Assistida/estatística & dados numéricos , Dissomia Uniparental , Adulto , Fatores Etários , Feminino , Humanos , Modelos Logísticos , Masculino , Idade Materna , Pessoa de Meia-Idade , Oócitos/metabolismo , Idade Paterna , Síndrome de Prader-Willi/etiologia , Técnicas de Reprodução Assistida/efeitos adversos , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Adulto Jovem
11.
Clin Genet ; 89(1): 115-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25810209

RESUMO

Wiedemann-Steiner syndrome (WSS) is an autosomal dominant congenital anomaly syndrome characterized by hairy elbows, dysmorphic facial appearances (hypertelorism, thick eyebrows, downslanted and vertically narrow palpebral fissures), pre- and post-natal growth deficiency, and psychomotor delay. WSS is caused by heterozygous mutations in KMT2A (also known as MLL), a gene encoding a histone methyltransferase. Here, we identify six novel KMT2A mutations in six WSS patients, with four mutations occurring de novo. Interestingly, some of the patients were initially diagnosed with atypical Kabuki syndrome, which is caused by mutations in KMT2D or KDM6A, genes also involved in histone methylation. KMT2A mutations and clinical features are summarized in our six patients together with eight previously reported patients. Furthermore, clinical comparison of the two syndromes is discussed in detail.


Assuntos
Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/genética , Histona-Lisina N-Metiltransferase/genética , Mutação , Proteína de Leucina Linfoide-Mieloide/genética , Fenótipo , Criança , Pré-Escolar , Exoma , Feminino , Loci Gênicos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino
12.
Rev Sci Instrum ; 86(5): 053503, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26026521

RESUMO

A neutron bang time and burn history monitor in inertial confinement fusion with fast ignition are necessary for plasma diagnostics. In the FIREX project, however, no detector attained those capabilities because high-intensity X-rays accompanied fast electrons used for plasma heating. To solve this problem, single-crystal CVD diamond was grown and fabricated into a radiation detector. The detector, which had excellent charge transportation property, was tested to obtain a response function for intense X-rays. The applicability for neutron bang time and burn history monitor was verified experimentally. Charge collection efficiency of 99.5% ± 0.8% and 97.1% ± 1.4% for holes and electrons were obtained using 5.486 MeV alpha particles. The drift velocity at electric field which saturates charge collection efficiency was 1.1 ± 0.4 × 10(7) cm/s and 1.0 ± 0.3 × 10(7) cm/s for holes and electrons. Fast response of several ns pulse width for intense X-ray was obtained at the GEKKO XII experiment, which is sufficiently fast for ToF measurements to obtain a neutron signal separately from X-rays. Based on these results, we confirmed that the single-crystal CVD diamond detector obtained neutron signal with good S/N under ion temperature 0.5-1 keV and neutron yield of more than 10(9) neutrons/shot.

14.
Phys Rev Lett ; 114(19): 195002, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26024175

RESUMO

A novel direct core heating fusion process is introduced, in which a preimploded core is predominantly heated by energetic ions driven by LFEX, an extremely energetic ultrashort pulse laser. Consequently, we have observed the D(d,n)^{3}He-reacted neutrons (DD beam-fusion neutrons) with the yield of 5×10^{8} n/4π sr. Examination of the beam-fusion neutrons verified that the ions directly collide with the core plasma. While the hot electrons heat the whole core volume, the energetic ions deposit their energies locally in the core, forming hot spots for fuel ignition. As evidenced in the spectrum, the process simultaneously excited thermal neutrons with the yield of 6×10^{7} n/4π sr, raising the local core temperature from 0.8 to 1.8 keV. A one-dimensional hydrocode STAR 1D explains the shell implosion dynamics including the beam fusion and thermal fusion initiated by fast deuterons and carbon ions. A two-dimensional collisional particle-in-cell code predicts the core heating due to resistive processes driven by hot electrons, and also the generation of fast ions, which could be an additional heating source when they reach the core. Since the core density is limited to 2 g/cm^{3} in the current experiment, neither hot electrons nor fast ions can efficiently deposit their energy and the neutron yield remains low. In future work, we will achieve the higher core density (>10 g/cm^{3}); then hot electrons could contribute more to the core heating via drag heating. Together with hot electrons, the ion contribution to fast ignition is indispensable for realizing high-gain fusion. By virtue of its core heating and ignition, the proposed scheme can potentially achieve high gain fusion.

16.
Neuroscience ; 295: 229-36, 2015 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-25818552

RESUMO

The striatum is a major target of cerebral cortical output. The cortico-striatal projection has been well described, however, the neurochemical changes that occur in the striatum after prolonged cortical hyperactivation remain to be investigated. In this study, extracellular levels of glutamate, GABA, and alanine levels were measured in the dorsal striatum using microdialysis in anesthetized mice at resting condition and during 4-aminopyridine (4-AP)-induced cortical seizures. After topical application of 4-AP on the primary motor cortex that induced cortical seizures, the extracellular level of striatal GABA increased by 40% in 60 min. By contrast, the extracellular level of striatal glutamate decreased by 20%. Moreover, the surface amounts of striatal glutamate/aspartate transporter (GLAST) and glutamate transporter 1 (GLT-1), the major astrocytic high-affinity glutamate transporters, tended to increase by cortical seizures in 60 min, suggesting a recruitment of the glutamate transporters from internal stores. 4-AP also resulted in a steady increase of alanine levels which are thought to reflect glutamate and pyruvate metabolism in neurons and astrocytes. These observations possibly delineate adaptive changes of striatal metabolism by severe cortical seizures.


Assuntos
Aminoácidos/metabolismo , Corpo Estriado/metabolismo , Líquido Extracelular/metabolismo , Córtex Motor/metabolismo , Convulsões/etiologia , Convulsões/patologia , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/fisiologia , Ampirona/toxicidade , Animais , Anti-Inflamatórios não Esteroides/toxicidade , Cromatografia Líquida de Alta Pressão , Corpo Estriado/efeitos dos fármacos , Modelos Animais de Doenças , Transportador 1 de Aminoácido Excitatório/metabolismo , Transportador 2 de Aminoácido Excitatório/metabolismo , Líquido Extracelular/efeitos dos fármacos , Lateralidade Funcional , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microdiálise , Córtex Motor/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/metabolismo
17.
J Tissue Eng Regen Med ; 9(1): 24-30, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23165985

RESUMO

The authors aimed to repair and regenerate articular cartilage with layered chondrocyte sheets, produced using temperature-responsive culture dishes. The purpose of this study was to investigate the humoral factors produced by layered chondrocyte sheets. Articular chondrocytes and synovial cells were harvested during total knee arthroplasty. After co-culture, the samples were divided into three groups: a monolayer, 7 day culture sheet group (group M); a triple-layered, 7 day culture sheet group (group L); and a monolayer culture group with a cell count identical to that of group L (group C). The secretion of collagen type 1 (COL1), collagen type 2 (COL2), matrix metalloproteinase-13 (MMP13), transforming growth factor-ß (TGFß), melanoma inhibitory activity (MIA) and prostaglandin E2 (PGE2) were measured by enzyme-linked immunosorbent assay (ELISA). Layered chondrocyte sheets produced the most humoral factors. PGE2 expression declined over time in group C but was significantly higher in groups M and L. TGFß expression was low in group C but was significantly higher in groups M and L (p<0.05). Our results suggest that the humoral factors produced by layered chondrocyte sheets may contribute to cartilaginous tissue repair and regeneration.


Assuntos
Condrócitos/citologia , Imunidade Humoral/fisiologia , Membrana Sinovial/citologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia do Joelho , Cartilagem Articular/citologia , Técnicas de Cultura de Células , Técnicas de Cocultura , Meios de Cultura , Dinoprostona/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Temperatura , Fator de Crescimento Transformador beta/metabolismo
18.
Rev Sci Instrum ; 85(11): 11D629, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430205

RESUMO

A photonuclear-reaction-based hard x-ray spectrometer is developed to measure the number and energy spectrum of fast electrons generated by interactions between plasma and intense laser light. In this spectrometer, x-rays are converted to neutrons through photonuclear reactions, and the neutrons are counted with a bubble detector that is insensitive to x-rays. The spectrometer consists of a bundle of hard x-ray detectors that respond to different photon-energy ranges. Proof-of-principle experiment was performed on a linear accelerator facility. A quasi-monoenergetic electron bunch (Ne = 1.0 × 10(-6) C, Ee = 16 ± 0.32 MeV) was injected into a 5-mm-thick lead plate. Bremsstrahlung x-rays, which emanate from the lead plate, were measured with the spectrometer. The measured spectral shape and intensity agree fairly well with those computed with a Monte Carlo simulation code. The result shows that high-energy x-rays can be measured absolutely with a photon-counting accuracy of 50%-70% in the energy range from 2 MeV to 20 MeV with a spectral resolution (Δhν/hν) of about 15%. Quantum efficiency of this spectrometer was designed to be 10(-7), 10(-4), 10(-5), respectively, for 2-10, 11-15, and 15-25 MeV of photon energy ranges.

19.
Rev Sci Instrum ; 85(11): 11E125, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430304

RESUMO

A multichannel low-energy neutron spectrometer for down-scattered neutron (DSN) measurements in inertial confinement fusion (ICF) experiments has been developed. Our compact-size 256-channel lithium-glass-scintillator-based spectrometer has been implemented and tested in ICF experiments with the GEKKO XII laser. We have performed time calibration of the 256-channel analog-to-digital convertor system used for DSN measurements via X-ray pulse signals. We have clearly observed the DD-primary fusion neutron signal and have successfully studied the detector's impulse response. Our detector is soon to be implemented in future ICF experiments.

20.
Rev Sci Instrum ; 85(11): 11E126, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430305

RESUMO

The characteristics of oxygen-enriched liquid scintillators with very low afterglow are investigated and optimized for application to a single-hit neutron spectrometer for fast ignition experiments. It is found that 1,2,4-trimethylbenzene has better characteristics as a liquid scintillator solvent than the conventional solvent, p-xylene. In addition, a benzophenon-doped BBQ liquid scintillator is shown to demonstrate very rapid time response, and therefore has potential for further use in neutron diagnostics with fast time resolution.

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