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This study was focused on the detection, characterization and virulence of a new baculovirus isolate from the larvae of cabbage looper, Trichoplusia ni (Hubner) (Lepidoptera: Noctuidae). T. ni is a polyphagous pest, and it has cosmopolitan distribution. An infected T. ni larvae was collected from a cabbage field in Turkey. Scanning electron microscopy studies showed the presence of typical occlusion bodies (OBs) with average size of 0.76 to 1.46 µm in the collected larvae. Since the virions have single nucleocapsid within the envelopes, the isolate was named as Trichoplusia ni single nucleopolyhedrovirus Turkey isolate (TrniSNPV- TR). The total genome of the TrniSNPV-TR was determined as 122.9 kb in size. Sequence analysis of the amplified late expression factor 8 (lef8), late expression factor 9 (lef9) and polyhedrin (polh) genes showed that the virus is a new isolate of nucleopolyhedroviruses and close to Trichoplusia ni SNPV isolates mentioned in the literature. However, this is the first study for the detection and characterization of a baculovirus from T. ni in Eurasian region. Insecticidal activities of the TrniSNPV-TR isolate (106 OBs/ml-1) against neonate, 3rd and 5th instar larvae of T. ni and Helicoverpa armigera showed 98%-91%, 91%-87% and 65%-60% mortalities, respectively, within 14 days. LC50 of TrniSNPV-TR was determined as 2×103-9×103, 3×104-7×104 and 1×105-2×105 OBs/ml on neonate, 3rd and 5th instar larvae, respectively. All these results showed that, TrniSNPV-TR has good potential to be utilized as a bio-pesticide against T. ni larvae in the future. Keywords: baculovirus; nucleopolyhedrovirus; Trichoplusia ni; TrniSNPV-TR; biological control.
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Mariposas , Nucleopoliedrovírus , Animais , Brassica , Larva , Mariposas/virologia , Nucleopoliedrovírus/classificação , Nucleopoliedrovírus/isolamento & purificação , Turquia , VirulênciaRESUMO
OBJECTIVE: Diagnosing fetal heart failure remains challenging because it is difficult to know how well the fetal myocardium will perform as loading conditions change. In adult cardiology, natriuretic peptides (NPs) are established markers of heart failure. However, the number of studies investigating NP levels in fetuses is quite limited. The aim of this study was to evaluate the significance of plasma NP levels in the assessment of heart failure in fetuses with a congenital heart defect (CHD) and/or arrhythmia. METHODS: This was a prospective observational study conducted at a tertiary pediatric cardiac center. A total of 129 singletons with CHD and/or arrhythmia and 127 controls were analyzed between 2012 and 2015. Umbilical cord plasma atrial NP, brain NP and N-terminal pro-brain NP levels at birth were compared with ultrasonography findings indicating fetal heart failure, such as cardiovascular profile (CVP) score and morphological characteristics. RESULTS: Fetuses with CHD and/or arrhythmia had higher NP levels than did controls (P < 0.01). NP levels of fetuses with CHD and/or arrhythmia were correlated inversely with CVP score (P for trend < 0.01). No differences in NP levels were found in fetuses with CHD and/or arrhythmia and a CVP score of ≥ 8 in comparison to controls. Multivariate analysis showed that a CVP score of ≤ 5, tachy- or bradyarrhythmia at birth, preterm birth and umbilical artery pH < 7.15 were associated independently with high NP levels (P < 0.01). Among fetuses with a CVP score of ≤ 7, abnormal venous Doppler sonography findings were significantly more common and more severe in fetuses with tachy- or bradyarrhythmia than in those with CHD, and those with tachy- or bradyarrhythmia had higher NP levels than did those with CHD (P = 0.01). Fetuses with right-heart defect and moderate or severe tricuspid valve regurgitation had significantly higher NP levels than did fetuses with other types of CHD (P < 0.01). CONCLUSIONS: Plasma NP levels in fetuses with CHD and/or arrhythmia are correlated with the severity of fetal heart failure. Elevated NP levels are attributed mainly to an increase in central venous pressure secondary to arrhythmia or atrioventricular valve regurgitation due to CHD, rather than to the morphological abnormality itself. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.
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Arritmias Cardíacas/sangue , Biomarcadores/sangue , Cardiopatias Congênitas/sangue , Insuficiência Cardíaca/sangue , Peptídeos Natriuréticos/sangue , Diagnóstico Pré-Natal , Adulto , Arritmias Cardíacas/congênito , Estudos de Coortes , Feminino , Insuficiência Cardíaca/congênito , Humanos , Valor Preditivo dos Testes , Gravidez , Resultado da Gravidez , Estudos ProspectivosRESUMO
Hepatitis B virus (HBV) reactivation has been reported during antihepatitis C treatment in patients with hepatitis C virus (HCV) and HBV co-infection. We aimed to evaluate the frequency and risk factors of HBV reactivation during anti-HCV therapy and compared those between interferon (IFN)-free direct-acting antiviral (DAA) therapies and IFN-based therapies. Three hundred and twenty-two patients with HCV infection receiving anti-HCV therapy were retrospectively screened. The baseline HBV infection statuses of all eligible patients and the HBV-DNA level of all patients with current or previous HBV infection were examined at the end of treatment. In patients with baseline anti-HBs positivity, changes in anti-HBs titre were evaluated. Of 287 patients who met the inclusion criteria, 157 had current (n=4) or previous (n=153) HBV infection; 85 were treated with IFN-free DAA therapies and 72 were treated with IFN-based therapies. Six patients experienced HBV reactivation (n=2) or HBV reappearance (n=4) after IFN-free DAA therapies, while no patient developed HBV reactivation after IFN-based therapies. The risk factors of HBV reactivation or reappearance were DAA therapies and a reduction in anti-HBs titre to <12 mIU mL-1 by the end of treatment. The decline changes of anti-HBs titre were significantly higher in patients treated with DAA therapies. Although HBV reactivation hepatitis was not observed, three of four patients with HBV reactivation or reappearance after achieving HCV eradication had viremia 8 weeks after completion of therapy. A significant proportion of patients develop HBV reactivation or reappearance without hepatitis after IFN-free DAA therapies. Low levels of anti-HBs and their decrease to <12 mIU mL-1 after treatment are significant risk factors for HBV reactivation or reappearance.
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Antivirais/uso terapêutico , Hepatite B Crônica/virologia , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Interferons/uso terapêutico , Ativação Viral , Adulto , Idoso , Idoso de 80 Anos ou mais , DNA Viral/sangue , Feminino , Hepatite B Crônica/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de RiscoRESUMO
Bright, short-pulsed neutron beams from laser-driven neutron sources (LANSs) provide a new perspective on material screening via fast neutron activation analysis (FNAA). FNAA is a nondestructive technique for determining material elemental composition based on nuclear excitation by fast neutron bombardment and subsequent spectral analysis of prompt γ-rays emitted by the active nuclei. Our recent experiments and simulations have shown that activation analysis can be used in practice with modest neutron fluences on the order of 105 n/cm2, which is available with current laser technology. In addition, time-resolved γ-ray measurements combined with picosecond neutron probes from LANSs are effective in mitigating the issue of spectral interference between elements, enabling highly accurate screening of complex samples containing many elements. This paper describes the predictive capability of LANS-based activation analysis based on experimental demonstrations and spectral calculations with Monte Carlo simulations.
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High energy density physics is the field of physics dedicated to the study of matter and plasmas in extreme conditions of temperature, densities and pressures. It encompasses multiple disciplines such as material science, planetary science, laboratory and astrophysical plasma science. For the latter, high energy density states can be accompanied by extreme radiation environments and super-strong magnetic fields. The creation of high energy density states in the laboratory consists in concentrating/depositing large amounts of energy in a reduced mass, typically solid material sample or dense plasma, over a time shorter than the typical timescales of heat conduction and hydrodynamic expansion. Laser-generated, high current-density ion beams constitute an important tool for the creation of high energy density states in the laboratory. Focusing plasma devices, such as cone-targets are necessary in order to focus and direct these intense beams towards the heating sample or dense plasma, while protecting the proton generation foil from the harsh environments typical of an integrated high-power laser experiment. A full understanding of the ion beam dynamics in focusing devices is therefore necessary in order to properly design and interpret the numerous experiments in the field. In this work, we report a detailed investigation of large-scale, kilojoule-class laser-generated ion beam dynamics in focusing devices and we demonstrate that high-brilliance ion beams compress magnetic fields to amplitudes exceeding tens of kilo-Tesla, which in turn play a dominant role in the focusing process, resulting either in a worsening or enhancement of focusing capabilities depending on the target geometry.
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A dosimetric calibration of three types of radiochromic films (GafChromicTM HD-V2, MD-V3, and EBT3) was carried out for absorbed doses (D) ranging up to 100 kGy using a 130 TBq Co60 γ-ray source. The optical densities (ODs) of the irradiated films were acquired with the transmission-mode flatbed film scanner EPSON GT-X980. The calibration data were cross-checked using the 20-MeV proton beam from the azimuthally varying field cyclotron at the Research Center for Nuclear Physics in Osaka University. These experimental results not only present the measurable dose ranges of the films depending on the readout wavelength, but also show consistency with our hypothesis that the OD response curve [log(OD)-log(D) curve] is determined by the volumetric average of the absorption dose and does not strongly depend on the type of radiation for the excitation.
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Receptor-mediated internalization and degradation of IL-2 were investigated in cell lines carrying human T cell leukemia/lymphoma (lymphotrophic) virus type I (HTLV-I) and PHA-treated normal PBL. The HTLV-I-carrying cell lines ILT-Yan and TL-Mor, and the PBL expressed both high- and low-affinity IL-2-R. However, another HTLV-I-carrying T cell line, MT-1, expressed mainly low-affinity receptors. Greater than 50% of the IL-2 bound to high-affinity receptors was internalized within 10 min when these cells were incubated at 37 degrees C. The internalized IL-2 was rapidly degraded and the products were excreted into the culture fluid. The t1/2 of IL-2 degradation in these cells was estimated as 60-80 min at 37 degrees C. The internalization and degradation of IL-2 were both temperature dependent. Light-microscopic autoradiography with 3H-labeled IL-2 confirmed the internalization of IL-2, and suggested that some IL-2 might be carried to the nucleus.
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Interleucina-2/metabolismo , Receptores Imunológicos/metabolismo , Linfócitos T/metabolismo , Compartimento Celular , Linhagem Celular , Transformação Celular Viral , Deltaretrovirus , Endocitose , Humanos , Concentração de Íons de Hidrogênio , Cinética , Receptores de Interleucina-2 , TemperaturaRESUMO
The objective of the present study was to establish a method for nuclear replacement in metaphase-II (M-II) stage porcine oocytes. Karyoplasts containing M-II chromosomes (K) and cytoplasts without chromosomes (C) were produced from in vitro-matured oocytes by a serial centrifugation method. The oocytes were then reconstructed by fusion of one karyoplast with 1, 2, 3 or 4 cytoplasts (K + 1C, K + 2C, K + 3C and K + 4C, respectively). Reconstructed oocytes, karyoplasts without fusion of any cytoplast (K) and zona-free M-II oocytes (control) were used for experiments. The rates of female pronucleus formation after parthenogenetic activation in all groups of reconstructed oocytes (58.2-77.4%) were not different from those of the K and control groups (58.2% and 66.0%, respectively). In vitro fertilization was carried out to assay the fertilization ability and subsequent embryonic development of the reconstructed oocytes. The cytoplast : karyoplast ratio did not affect the fertilization status (penetration and male pronuclear formation rates) of the oocytes. A significantly high monospermy rate was found in K oocytes (p < 0.05, 61.6%) compared with the other groups (18.2-32.8%). Blastocyst formation rates increased significantly as the number of the cytoplasts fused with karyoplasts increased (p < 0.05, 0.0-15.3%). The blastocyst rate in the K + 4C group (15.3%) was comparable with that of the control (17.8%). Total cell numbers in both the K + 3C and K + 4C groups (16.0 and 15.3 cells, respectively) were comparable with that of the control (26.2 cells). Our results demonstrate that a serial centrifugation and fusion (Centri-Fusion) is an effective method for producing M-II chromosome transferred oocytes with normal fertilization ability and in vitro development. It is suggested that the number of cytoplasts fused with a karyoplast plays a critical role in embryonic development.
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Núcleo Celular , Oócitos/fisiologia , Suínos/fisiologia , Animais , Blastocisto/fisiologia , Técnicas de Cultura Embrionária , Feminino , Fertilização in vitro , Masculino , Partenogênese/fisiologiaRESUMO
PURPOSE: To report the clinical efficacy and mid-term outcomes of endovascular treatment in patients with chronic, symptomatic, post-thrombotic femoro-iliac venous obstruction. MATERIALS AND METHODS: Forty-two patients with post-thrombotic syndrome (PTS) presenting with femoro-iliac venous obstructive lesions treated in our institution by endovascular approach between March 2012 and October 2017 were retrospectively included. There were 27 women and 15 men with a mean age of 47.3±17 (SD) years (range: 22-86 years). Procedure included first venous recanalization, then pre-dilatation and self-expandable metallic stenting of the narrowed or occluded iliac and/or femoral veins. Severity of PTS and quality of life were assessed at baseline and 3 months after the intervention respectively, using Villalta score and Chronic Venous Insufficiency Questionnaire (CIVIQ-20) scale. Imaging follow-up evaluation of stent patency was based on the results of duplex Doppler ultrasound and computed tomography. RESULTS: Immediate technical success was achieved in 41/42 (97.6%) patients, without any major complications. Primary patency, primary assisted patency and secondary patency at the end of the median imaging follow-up of 18.1 months (IQR, 9.7-34.4) were achieved in 29/42 (66.7%) patients, 33/42 (78.6%) patients and 37/42 (88.1%) patients, respectively. Median Villalta and CIVIQ-20 scores decreased from 14 (IQR, 10-19) and 57 (IQR, 39-72) at baseline, respectively, to 5 (IQR, 2-9) and 30 (IQR, 24-50) 3 months after the procedure, respectively (P<0.0001), showing significant decrease in the severity of PTS and improvement in the quality of life. The multiple linear regression model showed that both baseline Villalta and CIVIQ-20 scores ([95% CI: -7.80-3.79; P<0.0001] and [95% CI: 0.07-0.20; P<0.0001], respectively), age (95% CI: 0.04-0.19; P=0.002) and stenting expanse (95% CI: 0.97-5.65; P=0.006) were independent variables related to Villalta gain. Baseline Villalta (95% CI: 0.89-2.23; P<0.0001) was the single independent variable related to CIVIQ-20 gain. CONCLUSION: This study confirms the high clinical efficacy and favorable mid-term outcomes of endovascular stenting in patients with chronic symptomatic femoro-iliac venous obstructive lesions.
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Procedimentos Endovasculares , Veia Femoral , Veia Ilíaca , Stents , Trombose/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
The scientific and technical advances continue to support novel discoveries by allowing scientists to acquire new insights into the structure and properties of matter using new tools and sources. Notably, neutrons are among the most valuable sources in providing such a capability. At the Institute of Laser Engineering, Osaka, the first steps are taken towards the development of a table-top laser-driven neutron source, capable of producing a wide range of energies with high brightness and temporal resolution. By employing a pure hydrogen moderator, maintained at cryogenic temperature, a cold neutron ([Formula: see text]) flux of [Formula: see text]/pulse was measured at the proximity of the moderator exit surface. The beam duration of hundreds of ns to tens of [Formula: see text] is evaluated for neutron energies ranging from 100s keV down to meV via Monte-Carlo techniques. Presently, with the upcoming J-EPoCH high repetition rate laser at Osaka University, a cold neutron flux in orders of [Formula: see text] is expected to be delivered at the moderator in a compact beamline.
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Magnetic reconnection in a relativistic electron magnetization regime was observed in a laboratory plasma produced by a high-intensity, large energy, picoseconds laser pulse. Magnetic reconnection conditions realized with a laser-driven several kilotesla magnetic field is comparable to that in the accretion disk corona of black hole systems, i.e., Cygnus X-1. We observed particle energy distributions of reconnection outflow jets, which possess a power-law component in a high-energy range. The hardness of the observed spectra could explain the hard-state x-ray emission from accreting black hole systems.
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Relativistic electron temperatures were measured from kilojoule, subrelativistic laser-plasma interactions. Experiments show an order of magnitude higher temperatures than expected from a ponderomotive scaling, where temperatures of up to 2.2 MeV were generated using an intensity of 1×10^{18}W/cm^{2}. Two-dimensional particle-in-cell simulations suggest that electrons gain superponderomotive energies by stochastic acceleration as they sample a large area of rapidly changing laser phase. We demonstrate that such high temperatures are possible from subrelativistic intensities by using lasers with long pulse durations and large spatial scales.
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Paraplegia is one of the most tragic complications following endovascular aneurysm repair (EVAR) for descending thoracic aortic aneurysm (DTAA). Collateral circulation to the artery of Adamkiewicz (AA) is important to avoid spinal cord ischaemia. We report a case in which the thoracodorsal artery had become a collateral source to the AA. A 71-year-old man had undergone EVAR for DTAA. Three years after EVAR, an angiography demonstrated that the thoracodorsal artery had joined the 11th intercostal artery and had become a collateral source to the AA. The collateral circulation of thoracic wall arteries may play an important role in the postoperative spinal perfusion.
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Angioscopia/efeitos adversos , Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Circulação Colateral , Músculos Intercostais/irrigação sanguínea , Isquemia do Cordão Espinal/prevenção & controle , Artérias Torácicas/cirurgia , Idoso , Anastomose Cirúrgica/métodos , Angiografia , Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/diagnóstico por imagem , Vértebras Cervicais , Seguimentos , Humanos , Masculino , Paraplegia/etiologia , Paraplegia/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Reoperação , Isquemia do Cordão Espinal/complicações , Isquemia do Cordão Espinal/diagnóstico por imagem , Artérias Torácicas/diagnóstico por imagem , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVES: To determine the association between sarcopenia and overactive bladder (OAB) in elderly diabetic patients using the Japanese version of SARC-F called SARC-F-J. DESIGN: Cross-sectional study. SETTINGS AND PARTICIPANTS: The study included 329 elderly diabetic patients (aged ≥65 years) who regularly visited the outpatient clinic at Community hospital in Japan. MEASUREMENTS: The condition of OAB was evaluated using the OAM symptom score, which involves a self-administered questionnaire, and sarcopenia was evaluated using the self-administered SARC-F-J questionnaire comprising five items. The odds ratio for OAB due to sarcopenia was calculated using multiple logistic regression analysis, with OAB as the dependent variable and sarcopenia as the explanatory variable. RESULTS: A total of 329 patients (186 males, 143 females) were included for analysis in the present study. Of these patients, 22.9% had sarcopenia and 18.7% had OAB. After adjusting the variables, the odds ratio for OAB due to sarcopenia was 4.46 (95% confidence interval [CI], 1.14-17.36, P = 0.031) and 2.09 (95% CI, 0.52-8.26, P = 0.293) for males and females, respectively. CONCLUSION: This study found that sarcopenia was significantly associated with OAB in elderly diabetic male patients based on SARC-F-J. Moreover, the possibility of the development of OAB should be considered during the medical examinations of elderly diabetic male patients with sarcopenia.
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Complicações do Diabetes/complicações , Sarcopenia/complicações , Bexiga Urinária Hiperativa/etiologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: Sesamin is a major lignan constituent of sesame and possesses various health-promoting effects. Previous studies have demonstrated that sesamin extends the lifespan of Drosophila and Caenorhabditis elegans and corrects oxidative damage-related tissue dysfunction in mammals. To understand its anti-aging effects, we aimed to determine whether sesamin restores tissue function hampered by oxidative damage and suppresses several aging-related phenotypes using Drosophila senescence-accelerated models. MATERIALS AND METHODS: We elucidated the anti-aging effects of sesamin on several aging-related phenotypes in the muscle, brain and midgut using the senescence-accelerated models (Sod1n1 mutant and Sod1-depleted flies) by immunostaining experiments. We determined the expression levels of several anti-oxidative and DNA repair genes using quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). We also identified the metabolite of sesamin in Drosophila by LC-MS/MS. RESULTS: We confirmed that sesamin (0.35 and 2 mg/ml) extended the lifespan of the fly models. As observed in mammals, it can be absorbed and metabolized by Drosophila adults. The sesamin feeding suppressed the age-dependent impairment of locomotor activity and inhibited the accumulation of reactive oxygen species (ROS) in their bodies. Sesamin delayed the age-dependent accumulation of damaged proteins in the muscle, partially suppressed the loss of dopaminergic neurons in adult brains displaying ROS accumulation, and suppressed the accumulation of DNA damage and hyperproliferation of intestinal stem cells. Four antioxidative genes and two DNA repair genes were simultaneously upregulated in sesamin-fed adults. CONCLUSIONS: These observations represent the first direct evidence of the anti-aging effects of sesamin at the individual level. We propose that sesamin exerts anti-aging effects in the muscles, brain and midgut by inducing antioxidative and DNA repair genes, resulting in extended lifespan in flies.
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Envelhecimento/efeitos dos fármacos , Antioxidantes/farmacologia , Dioxóis/farmacologia , Modelos Animais de Doenças , Drosophila melanogaster , Intestinos , Lignanas/farmacologia , Longevidade , Envelhecimento/genética , Animais , Antioxidantes/análise , Antioxidantes/metabolismo , Células Cultivadas , Cromatografia Líquida , Dioxóis/análise , Dioxóis/metabolismo , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Intestinos/efeitos dos fármacos , Lignanas/análise , Lignanas/metabolismo , Músculos/efeitos dos fármacos , Músculos/metabolismo , Sistema Nervoso/efeitos dos fármacos , Sistema Nervoso/metabolismo , Fenótipo , Superóxido Dismutase/deficiência , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Espectrometria de Massas em TandemRESUMO
Innovation has been the cornerstone of interventional radiology since the early years of the founders, with a multitude of new therapeutic approaches developed over the last 50 years. What is the future holding for us? This article presents an overview of the in-coming developments that are catching on at this moment, particularly focusing on three items: the new applications of existing techniques, particularly embolotherapy and interventional oncology; the cutting-edge devices; the imaging technologies at the forefront of the image-guidance. Besides this, clinical vision and patient relation remain crucial for the future of the discipline.
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Increasing the laser energy absorption into energetic particle beams represents a longstanding quest in intense laser-plasma physics. During the interaction with matter, part of the laser energy is converted into relativistic electron beams, which are the origin of secondary sources of energetic ions, γ-rays and neutrons. Here we experimentally demonstrate that using multiple coherent laser beamlets spatially and temporally overlapped, thus producing an interference pattern in the laser focus, significantly improves the laser energy conversion efficiency into hot electrons, compared to one beam with the same energy and nominal intensity as the four beamlets combined. Two-dimensional particle-in-cell simulations support the experimental results, suggesting that beamlet interference pattern induces a periodical shaping of the critical density, ultimately playing a key-role in enhancing the laser-to-electron energy conversion efficiency. This method is rather insensitive to laser pulse contrast and duration, making this approach robust and suitable to many existing facilities.
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In vitro fertilization (IVF) of in vitro matured (IVM) oocytes in pigs has become the most popular method of studying gametogenesis and embryogenesis in this species. Furthermore, because of recent advances in in vitro culture (IVC) of IVM-IVF embryos, in vitro production (IVP) of embryos now enables us to generate viable embryos as successfully as for in vivo-derived embryos and with less cost and in less time. These technologies contribute not only to developments in reproductive physiology and agriculture but also to the conservation of porcine genetic resources and the production of cloned or genetically modified pigs. However, in IVP, there still remains the problem of abnormal ploidy, which is caused by performing procedures under non-physiological conditions. In recent years, unique technologies such as intracytoplasmic sperm injection (ICSI) or xenografting of gonadal tissue into immunodeficient experimental animals have been developed to help conserve gamete resources. These technologies combined with IVP are expected to be useful for the conservation of gametes from important genetic resources. Here, we discuss the developmental ability and normality of porcine IVP embryos and also the utilization of ICSI and xenografting in advancing biotechnology in pigs.
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Fertilização in vitro/veterinária , Gametogênese/fisiologia , Injeções de Esperma Intracitoplásmicas/veterinária , Suínos/fisiologia , Animais , Conservação dos Recursos Naturais , Transferência Embrionária/métodos , Transferência Embrionária/veterinária , Feminino , Fertilização in vitro/métodos , Masculino , Gravidez , Injeções de Esperma Intracitoplásmicas/métodos , Suínos/genética , Transplante HeterólogoRESUMO
A design of multichannel gated photomultiplier tube (PMT) is presented for the 960-channel neutron time-of-flight detector at the Institute of Laser Engineering of Osaka University. This is important for the fusion science and the nuclear photonics where intense hard X-rays are generated from the interaction of ultra-short laser pulse of petawatt power density with matter. The hard X-rays often overload PMTs and cause signal-induced background noises called afterpulses, making the detection of subsequent neutrons impossible. For this reason, the PMTs are coupled with an electrical time-gating (ETG) system to avoid overloading. The ETG system disables the PMT by modulating the dynode potential during the primary X-ray flash. An after-pulsing suppression technique is demonstrated by applying a reverse bias voltage between the photocathode and the first dynode. The presented multichannel scheme provides a gate response time of 80 ns, a signal cutoff ratio of 2.5 × 102, and requires reasonably low power consumption.
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A large-aperture high-sensitivity image intensifier panel that consists of an avalanche photodiode array and a light-emitting diode array is presented. The device has 40% quantum efficiency, over 104 optical gain, and 80-ns time resolution. The aperture size of the device is 20 cm, and with the current manufacturing process, it can be scaled to arbitrarily larger sizes. The device can intensify the light from a single particle scintillation emission to an eye-visible bright flash. The image resolution of the device is currently limited by the size of the avalanche photodiode that is 2 mm, although it can be scaled to smaller sizes in the near future. The image intensifier is operated at a small voltage, typically +57 V. The device can be applied to various applications, such as scintillation imaging, night vision cameras, and an image converter from non-visible light (such as infrared or ultraviolet) to visible light.