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1.
Phys Rev Lett ; 127(24): 245001, 2021 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-34951808

RESUMEN

In inertial confinement approaches to fusion, the asymmetry of target implosion is a major obstacle to achieving high gain in the laboratory. A recently proposed octahedral spherical hohlraum makes it possible to naturally create spherical target irradiation without supplementary symmetry control. Before any decision is made to pursue an ignition-scale laser system based on the octahedral hohlraum, one needs to test the concept with the existing facilities. Here, we report a proof-of-concept experiment for the novel octahedral hohlraum geometry on the cylindrically configured SGIII laser facility without a symmetry control. All polar and equatorial self-emission images of the compressed target show a near round shape of convergence ratio 15 under both square and shaped laser pulses. The observed implosion performances agree well with the ideal spherical implosion simulation. It also shows limitations with using the existing facilities and adds further weight to the need to move to a spherical port geometry for future ignition laser facilities.

2.
Neurol Sci ; 40(12): 2617-2624, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31392639

RESUMEN

BACKGROUND AND AIMS: Whether fluid-attenuated inversion recovery (FLAIR) vascular hyperintensities (FVH)-DWI mismatch could predict the outcome or not remains in debate. The aim of this study was to identify if FVH combined with the other markers improved favorable outcome prediction of acute infarctions in patients with unilateral acute internal carotid artery (ICA) occlusion. METHODS: Consecutive 68 adult acute middle cerebral artery (MCA) territory infarction patients caused by acute ICA occlusion, including favorable (n = 38, mRS ≤ 2) and unfavorable (n = 30, mRS > 2) groups, were enrolled in this retrospective analysis. The diagnostic efficiency of favorable clinical outcome of FVH-DWI mismatch was compared with those of DWI lesions volumetry and the combined marker of FVH-DWI mismatch and other factors. RESULTS: There were more prominent FVH-DWI mismatch (≥ 3 sections) (84%), less atrial fibrillation (AFib) (13%), and more tandem MCA normal or mild stenosis (63%) in favorable outcome group than those (30%, 40%, and 27%, respectively) in unfavorable group. Univariate and multivariate analyses showed that the prominent FVH-DWI mismatch was the positive predictive factor for favorable outcome (OR = 2.643 and 3.200). Prominent FVH-DWI mismatch, in combination with tandem MCA normal or mild stenosis, and absence of Afib, had better performance (AUC = 0.875) than that of initial DWI lesion volumetry (AUC = 0.854) and any other single factor (AUC = 0.634~0.820) in predicting favorable outcome. CONCLUSIONS: Prominent FVH-DWI mismatch was associated with favorable outcome in acute infarctions in unilateral ICA occlusion patients. Its predictive performance would be improved when combined with the assessment of tandem lesions of MCA and AFib.


Asunto(s)
Fibrilación Atrial/diagnóstico , Estenosis Carotídea/diagnóstico , Infarto de la Arteria Cerebral Media/diagnóstico , Imagen por Resonancia Magnética/normas , Evaluación de Resultado en la Atención de Salud , Enfermedad Aguda , Anciano , Fibrilación Atrial/terapia , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/terapia , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Infarto de la Arteria Cerebral Media/terapia , Angiografía por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
3.
Acta Radiol ; 60(5): 628-633, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30130971

RESUMEN

BACKGROUND: Evaluating the acute ischemic volume on diffusion-weighted imaging (DWI) in the middle cerebral artery (MCA) territory would predict outcome. PURPOSE: To investigate the correlations between maximum area with restricted diffusion (MaxA), the orthogonal diameters (OD) as well as lesion volume on DWI, and to explore the role of MaxA and OD on predicting unfavorable outcome after an acute MCA ischemic stroke. MATERIAL AND METHODS: Sixty consecutive adult patients, including modified Rankin Scale score (mRS) ≤2 (n = 31) and mRS > 2 (n = 29) groups, were retrospectively enrolled. The MaxA and OD of lesions were assessed at the slice containing the largest infarction size on DWI images. We compared the prediction efficiencies of these methods on unfavorable outcomes. RESULTS: The correlation coefficients between the MaxA and infarction volume and OD and infarction volume were 0.982 ( P < 0.001) and 0.952 ( P < 0.001), respectively. The times required for measuring MaxA (150 s [130-160]) and OD (30 s [20-60]) were much shorter than that for infarction volume measurement (1240 s [180-1480]) ( P = 0.001, P = 0.004). With thresholds of ≥57.3 mL for infarction volume, ≥15.2 cm2 for MaxA, and ≥38.1 for the arithmetic product of OD, the AUCs of infarction volume, MaxA, and OD for predicting an unfavorable outcome were 0.818, 0.821, and 0.820, respectively. CONCLUSION: Since they correlated well with the infarction volume, MaxA and OD assessed on DWI were time-saving and achieved comparable diagnostic efficiencies; thus, they may represent alternative imaging markers for predicting unfavorable outcomes of acute ischemic stroke in MCA territory.


Asunto(s)
Isquemia Encefálica/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética/métodos , Arteria Cerebral Media/diagnóstico por imagen , Arteria Cerebral Media/patología , Accidente Cerebrovascular/diagnóstico por imagen , Isquemia Encefálica/complicaciones , Isquemia Encefálica/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/patología
4.
Phys Rev Lett ; 120(16): 165001, 2018 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-29756949

RESUMEN

The first octahedral spherical hohlraum energetics experiment is accomplished at the SGIII laser facility. For the first time, the 32 laser beams are injected into the octahedral spherical hohlraum through six laser entrance holes. Two techniques are used to diagnose the radiation field of the octahedral spherical hohlraum in order to obtain comprehensive experimental data. The radiation flux streaming out of laser entrance holes is measured by six flat-response x-ray detectors (FXRDs) and four M-band x-ray detectors, which are placed at different locations of the SGIII target chamber. The radiation temperature is derived from the measured flux of FXRD by using the blackbody assumption. The peak radiation temperature inside hohlraum is determined by the shock wave technique. The experimental results show that the octahedral spherical hohlraum radiation temperature is in the range of 170-182 eV with drive laser energies of 71 kJ to 84 kJ. The radiation temperature inside the hohlraum determined by the shock wave technique is about 175 eV at 71 kJ. For the flat-top laser pulse of 3 ns, the conversion efficiency of gas-filled octahedral spherical hohlraum from laser into soft x rays is about 80% according to the two-dimensional numerical simulation.

5.
J Magn Reson Imaging ; 48(4): 964-970, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29424126

RESUMEN

BACKGROUND: Outcome prediction of asymmetrical prominent cortical veins (APCVs) on infarction is still debated and may help in selecting patients for reperfusion treatment. PURPOSE: To explore the relationship between fewer peripheral APCVs and the outcome in the patients of acute/subacute middle cerebral artery (MCA) infarctions as well as the relationship between this sign and stenosis of ipsilateral MCA. STUDY TYPE: Retrospective case-control study. POPULATION: We enrolled 41 patients with MCA acute/subacute infarction. Compared to the low sign of cortical veins of contralateral hemisphere on susceptibility-weighted imaging (SWI), these patients were divided into fewer (n = 28) and prominent APCVs (n = 13) groups. FIELD STRENGTH/SEQUENCE: 3.0T conventional stroke sequences, including T1 -weighted imaging, T2 -weighted imaging, fluid-attenuated inversion recovery (FLAIR), diffusion-weighted imaging (DWI) (b = 0 and 1000 s/mm2 ), MR angiography (MRA), and SWI. ASSESSMENT: We explored the relationships between fewer peripheral APCVs sign and clinical outcome, as well as the relationship between this sign and the degree of ipsilateral MCA stenosis. STATISTICAL TESTS: Fisher's exact analysis, logistical regression, as well as Cohen's kappa coefficient were used for statistical analysis. RESULTS: Fewer and prominent peripheral APCVs were detected in 28 (56.10%) and 13 (43.90%) patients. In 28 patients with fewer peripheral APCVs, 23 patients (82.14%) had a favorable outcome (modified Rankin Scale [mRS] ≤2), and five patients (17.76%) had an unfavorable outcome (mRS >2) (P = 0.010). In terms of MCA stenosis, the rate of normal and mild to moderate stenosis of MCA in the fewer APCVs group (82.14%) was higher than that in the prominent APCVs group (23.08%) (P < 0.001). More severe stenosis of ipsilateral MCA was found in patients with prominent APCVs group (76.92%) than that of fewer APCVs group (17.86%). The peripheral APCVs was positively correlated with the degree of MCA stenosis (r = 0.538, P < 0.001). DATA CONCLUSION: Fewer peripheral APCVs may suggest a favorable outcome in unilateral MCA infarction. The patency of ipsilateral MCA may correlate to fewer APCVs and favorable outcome. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2018;48:964-970.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Imagen por Resonancia Magnética , Arteria Cerebral Media/diagnóstico por imagen , Anciano , Estudios de Casos y Controles , Constricción Patológica , Bases de Datos Factuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reperfusión , Estudios Retrospectivos , Resultado del Tratamiento
6.
Phys Rev Lett ; 117(2): 025002, 2016 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-27447512

RESUMEN

The first spherical hohlraum energetics experiment is accomplished on the SGIII-prototype laser facility. In the experiment, the radiation temperature is measured by using an array of flat-response x-ray detectors (FXRDs) through a laser entrance hole at four different angles. The radiation temperature and M-band fraction inside the hohlraum are determined by the shock wave technique. The experimental observations indicate that the radiation temperatures measured by the FXRDs depend on the observation angles and are related to the view field. According to the experimental results, the conversion efficiency of the vacuum spherical hohlraum is in the range from 60% to 80%. Although this conversion efficiency is less than the conversion efficiency of the near vacuum hohlraum on the National Ignition Facility, it is consistent with that of the cylindrical hohlraums used on the NOVA and the SGIII-prototype at the same energy scale.

7.
Opt Express ; 23(19): A1072-80, 2015 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-26406737

RESUMEN

A space-resolving flux detector (SRFD) is developed to measure the X-ray flux emitted from a specified region in hohlraum with a high resolution up to 0.11mm for the first time. This novel detector has been used successfully to measure the distinct X-ray fluxes emitted from hot laser spot and cooler re-emitting region simultaneously, in the hohlraum experiments on SGIII prototype laser facility. According to our experiments, the ratio of laser spot flux to re-emitted flux shows a strong time-dependent behavior, and the area-weighted flux post-processed from the measured laser spot flux and re-emitting wall flux agrees with that measured from Laser Entrance Hole by using flat-response X-ray detector (F-XRD). The experimental observations is reestablished by our two-dimensional hydrodynamic simulations and is well understood with the power balance relationship.

8.
Zhonghua Fu Chan Ke Za Zhi ; 50(5): 367-73, 2015 May.
Artículo en Zh | MEDLINE | ID: mdl-26311457

RESUMEN

OBJECTIVE: To investigate the production and mechanism of chemokine (C-C motif) ligand 5 (CCL5) by macrophages in U14 cervical cancer-bearing mice during infection. METHODS: The U14 cervical cancer cells were injected in C57BL/6 mice to induce tumor-bearing condition. Lipopolysaccharide (LPS) was injected into C57BL/6 mice to induce infection. The protein expression of CCL5 in the serum and the CCL5 mRNA expression in inflammatory cells were measured by ELISA and fluorescence quantitative-PCR in four groups. Macrophages were induced in the tumor conditioned medium (TCM) which extracted from mice serum. The protein expression levels of CCL5, prostaglandin E2 (PGE2) and cyclic adenosine monophosphate (cAMP) in the medium and CCL5, PGE2 and cAMP mRNA expression in the macrophages were detected in different groups. In order to determine whether the inhibition was related to PGE2, selective cyclooxygenase 2(COX-2) inhibitor NS398 was used to reverse this phenomenon and protein kinase A (PKA) inhibitor H89 demonstrated the mechanism through blocking cAMP/PKA signaling pathway. RESULTS: (1) The protein and mRNA level of CCL5 in tumor-bearing mice were respectively (151 ± 35) pg/ml and 1.0, which were lower than those in the tumor-free mice (691 ± 85) pg/ml and 4.5 ± 0.8, there were significant difference between them (all P < 0.05). The protein and mRNA level of PGE2 in tumor-bearing mice were (1 198 ± 83) pg/ml and 5.8 ± 0.8, which were higher than those in the tumor-free mice (187 ± 25) pg/ml and 1.0, the difference were significant (all P < 0.05). The protein and mRNA level of CCL5 in tumor-free + LPS mice were (4 049 ± 141) pg/ml and 31.5 ± 2.0, which were higher than those in the tumor-bearing + LPS mice (1 951 ± 71) pg/ml and 12.1 ± 2.8, the difference were also significant (P < 0.05). The protein and mRNA level of PGE2 in tumor-free + LPS mice were (676 ± 70) pg/ml and 3.4 ± 0.4, which were lower than those in tumor-bearing + LPS mice (2 550 ± 382) pg/ml and 11.6 ± 0.9, the difference were also significant (all P < 0.05). (2) Macrophages were cultured in vitro using TCM derived from mice. The protein and mRNA level of CCL5 in tumor-bearing mice TCM were respectively (1 626 ± 177) pg/ml and 28.6 ± 1.2, which were higher than those in the tumor-free mice TCM [(27 ± 3) pg/ml and 1.0], there were significant difference (P < 0.05). The protein and mRNA level of PGE2 in tumor-bearing mice TCM were (790 ± 156) pg/ml and 1.7 ± 0.3, which were higher than those in the tumor-free mice TCM [(448 ± 115) pg/ml, 1.0], the difference were significant (all P < 0.05). The protein and mRNA level of cAMP in tumor-bearing mice TCM were (164 ± 30) pg/ml and 1.6 ± 0.3, which weres higher than those in the tumor-free mice TCM [(118 ± 25) pg/ml,1.0], the difference were significant (all P < 0.05). The protein and mRNA level of CCL5 in tumor-free + LPS mice TCM were (10 475 ± 742) pg/ml and 212.0 ± 5.7, which were higher than those in the tumor-bearing + LPS mice TCM [(6 375 ± 530) pg/ml, 142.3 ± 2.5], the difference were significant (all P < 0.05). The protein and mRNA level of PGE2 in tumor-free + LPS mice TCM were (2 438 ± 95) pg/ml and 4.3 ± 0.7, which weres lower than those in the tumor-bearing + LPS mice TCM [(3 441 ± 163) pg/ml, 5.9 ± 0.3], the difference were significant (all P < 0.05). The protein and mRNA level of cAMP in tumor-free + LPS mice TCM were (340 ± 13) pg/ml and 4.1 ± 0.4, which were lower than those in the tumor-bearing + LPS mice TCM [(542 ± 42) pg/ml, 5.4 ± 0.5], the difference were significant (all P < 0.05). (3) Using COX-2 inhibitor NS398 in the tumor-bearing + LPS mice, the protein and mRNA level of CCL5, PGE2 and cAMP were (7 691 ± 269) pg/ml and 159.0 ± 8.9, (2 820 ± 152) pg/ml and 4.9 ± 0.3, (465 ± 8) pg/ml and 4.3 ± 0.4, respectively, and there were significant difference (all P < 0.05), compared to before treatment. Using PKA inhibitor H89 in the tumor-bearing + LPS mice, the protein and mRNA level of CCL5, PGE2 and cAMP were (8 375 ± 520) pg/ml and 177.0 ± 8.8, (2 650 ± 35) pg/ml and 4.7 ± 0.4, (368 ± 13) pg/ml and 3.1 ± 0.7, respectively, and there were significant difference (all P < 0.05), compared to before treatment. CONCLUSION: TCM of U14 cells activated macrophages to release PGE2 could inhibit the expression of CCL5 levels by cAMP/PKA signaling pathway.


Asunto(s)
Quimiocina CCL5/metabolismo , AMP Cíclico/metabolismo , Dinoprostona/metabolismo , ARN Mensajero/genética , Neoplasias del Cuello Uterino/sangre , Animales , Quimiocina CCL5/sangre , Medios de Cultivo Condicionados , Ciclooxigenasa 2 , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Lipopolisacáridos , Macrófagos , Ratones , Ratones Endogámicos C57BL , Nitrobencenos , Reacción en Cadena de la Polimerasa , Transducción de Señal , Sulfonamidas , Neoplasias del Cuello Uterino/metabolismo
9.
Acta Radiol Open ; 12(1): 20584601231152640, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36699098

RESUMEN

Horseshoe lung (HL) is an infrequent congenital lung anomaly. Its main feature is that the lower lungs on both sides extend behind the pericardium and fuse across the midline, usually accompanied by pulmonary dysplasia. It is reported that 80% of HL is relevant to the abnormal return of some pulmonary veins from the right lung to the inferior vena cava or right atrium (scimitar syndrome). Most patients are within 5 years old, most commonly within 1 year old, but HL may also have no apparent clinical symptoms or mild symptoms. This case is a 36-years-old adult female who developed left chest pain more than a month ago and continued to worsen for 10 days. The patient also had repeated pulmonary infection with cough and expectoration.

10.
Phys Rev Lett ; 109(14): 145004, 2012 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-23083253

RESUMEN

The proposal of simultaneously determining the hohlraum peak radiation temperature T(R) and M-band fraction f(M) by shock velocity measurement technique [Y. S. Li et al. Phys. Plasmas 18, 022701 (2011)] is demonstrated for the first time in recent experiments conducted on SGIII-prototype laser facility. In the experiments, T(R) and f(M) are determined by using the observed shock velocities in Al and Ti. For the Au hohlraum used in the experiments, T(R) is about 160 eV and f(M) is around 4.3% under a 1 ns laser pulse of 2 kJ. The results from this method are complementary to those from the broadband x-ray spectrometer, and the technique can be further used to determine T(R) and f(M) inside an ignition hohlraum.

11.
Sci Rep ; 9(1): 5050, 2019 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-30911070

RESUMEN

This study explores the radiation field temperatures introduced by the laser spot, the re-emitting wall in a hohlraum and the entire hohlraum drive source. This investigation, which is the first of its kind, is based on the radiation fluxes from the laser spot and the re-emitting wall, which have been accurately measured using time- and space-resolving flux detectors in a recent work, and additional flux data. The temperature difference between the laser spot and the entire hohlraum drive source was 6.08-35.35% of the temperature of the latter throughout the entire laser pulse, whilst that for the re-emitting wall was 3.90-12.81%. The radiation temperature of the cooler re-emitting wall had more influence on the temperature increase of the entire hohlraum drive source than the hot laser-spot temperature, which has been quantitatively discussed. Experimentally, we established the average distributions of the temperature fields of all the emitting sources, namely laser spot and re-emitting wall, of the irradiating fluxes on the capsule region in the hohlraum radiation field. This important progress in the exploration of radiation temperature distributions within a hohlraum will provide a foundation for determination of the irradiating radiation on the capsule and evaluation of capsule symmetry.

12.
Rev Sci Instrum ; 89(6): 063502, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29960517

RESUMEN

Space-resolving flux detection is an important technique for the diagnostic of the radiation field within the hohlraum in inertial confinement fusion, especially for the radiation field diagnostic in the novel spherical hohlraum with octahedral six laser entrance holes (LEHs), where localized measurements are necessary for the discrimination of the radiation flux from different LEHs. A novel space-resolving flux detector (SRFD) is developed at the SG-III laser facility for the radiation flux measurement in the first campaign of the octahedral spherical hohlraum energetics experiment. The principle and configuration of the SRFD system is introduced. The radiation flux from the wall of a gas-filled octahedral spherical hohlraum is measured for the first time by placing the SRFD system at the equatorial position of the SG-III laser facility, aiming at the hohlraum wall through one of the six LEHs. The absolute radiation flux from the re-emission area on the hohlraum wall is measured, and good consistency is found between the experimental data and the calculated data from a three-dimensional view factor analysis.

13.
Rev Sci Instrum ; 88(8): 083115, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28863660

RESUMEN

X-ray imaging plates are one of the most important X-ray imaging detectors and are widely used in inertial-confinement fusion experiments. However, their linear response range, which is the foundation of their quantitative data analysis, has not been sufficiently deeply investigated. In this work, we develop an X-ray fluorescer calibration system and carefully explore the linear response range of X-ray imaging plates. For the first time, nearly the entire grayscale range of the X-ray imaging plate linear response-7819-64 879 in the range of 0-65 535-has been observed. Further, we discuss the uncertainties involved in the calibration process. This work demonstrates the excellent linear response qualities of X-ray imaging plates and provides a significant foundation for expanding their quantitative applied range.

14.
Phys Rev E ; 95(3-1): 031202, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28415291

RESUMEN

Octahedral spherical hohlraums with a single laser ring at an injection angle of 55^{∘} are attractive concepts for laser indirect drive due to the potential for achieving the x-ray drive symmetry required for high convergence implosions. Laser-plasma instabilities, however, are a concern given the long laser propagation path in such hohlraums. Significant stimulated Raman scattering has been observed in cylindrical hohlraums with similar laser propagation paths during the ignition campaign on the National Ignition Facility (NIF). In this Rapid Communication, experiments demonstrating low levels of laser-driven plasma instability (LPI) in spherical hohlraums with a laser injection angle of 55^{∘} are reported and compared to that observed with cylindrical hohlraums with injection angles of 28.5^{∘} and 55^{∘}, similar to that of the NIF. Significant LPI is observed with the laser injection of 28.5^{∘} in the cylindrical hohlraum where the propagation path is similar to the 55^{∘} injection angle for the spherical hohlraum. The experiments are performed on the SGIII laser facility with a total 0.35-µm incident energy of 93 kJ in a 3 nsec pulse. These experiments demonstrate the role of hohlraum geometry in LPI and demonstrate the need for systematic experiments for choosing the optimal configuration for ignition studies with indirect drive inertial confinement fusion.

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